statement of hypothesis or theory

This is the Difference Between a Hypothesis and a Theory

What to Know A hypothesis is an assumption made before any research has been done. It is formed so that it can be tested to see if it might be true. A theory is a principle formed to explain the things already shown in data. Because of the rigors of experiment and control, it is much more likely that a theory will be true than a hypothesis.

As anyone who has worked in a laboratory or out in the field can tell you, science is about process: that of observing, making inferences about those observations, and then performing tests to see if the truth value of those inferences holds up. The scientific method is designed to be a rigorous procedure for acquiring knowledge about the world around us.

In scientific reasoning, a hypothesis is constructed before any applicable research has been done. A theory, on the other hand, is supported by evidence: it's a principle formed as an attempt to explain things that have already been substantiated by data.

Toward that end, science employs a particular vocabulary for describing how ideas are proposed, tested, and supported or disproven. And that's where we see the difference between a hypothesis and a theory .

A hypothesis is an assumption, something proposed for the sake of argument so that it can be tested to see if it might be true.

In the scientific method, the hypothesis is constructed before any applicable research has been done, apart from a basic background review. You ask a question, read up on what has been studied before, and then form a hypothesis.

What is a Hypothesis?

A hypothesis is usually tentative, an assumption or suggestion made strictly for the objective of being tested.

When a character which has been lost in a breed, reappears after a great number of generations, the most probable hypothesis is, not that the offspring suddenly takes after an ancestor some hundred generations distant, but that in each successive generation there has been a tendency to reproduce the character in question, which at last, under unknown favourable conditions, gains an ascendancy. Charles Darwin, On the Origin of Species , 1859 According to one widely reported hypothesis , cell-phone transmissions were disrupting the bees' navigational abilities. (Few experts took the cell-phone conjecture seriously; as one scientist said to me, "If that were the case, Dave Hackenberg's hives would have been dead a long time ago.") Elizabeth Kolbert, The New Yorker , 6 Aug. 2007

What is a Theory?

A theory , in contrast, is a principle that has been formed as an attempt to explain things that have already been substantiated by data. It is used in the names of a number of principles accepted in the scientific community, such as the Big Bang Theory . Because of the rigors of experimentation and control, its likelihood as truth is much higher than that of a hypothesis.

It is evident, on our theory , that coasts merely fringed by reefs cannot have subsided to any perceptible amount; and therefore they must, since the growth of their corals, either have remained stationary or have been upheaved. Now, it is remarkable how generally it can be shown, by the presence of upraised organic remains, that the fringed islands have been elevated: and so far, this is indirect evidence in favour of our theory . Charles Darwin, The Voyage of the Beagle , 1839 An example of a fundamental principle in physics, first proposed by Galileo in 1632 and extended by Einstein in 1905, is the following: All observers traveling at constant velocity relative to one another, should witness identical laws of nature. From this principle, Einstein derived his theory of special relativity. Alan Lightman, Harper's , December 2011

Non-Scientific Use

In non-scientific use, however, hypothesis and theory are often used interchangeably to mean simply an idea, speculation, or hunch (though theory is more common in this regard):

The theory of the teacher with all these immigrant kids was that if you spoke English loudly enough they would eventually understand. E. L. Doctorow, Loon Lake , 1979 Chicago is famous for asking questions for which there can be no boilerplate answers. Example: given the probability that the federal tax code, nondairy creamer, Dennis Rodman and the art of mime all came from outer space, name something else that has extraterrestrial origins and defend your hypothesis . John McCormick, Newsweek , 5 Apr. 1999 In his mind's eye, Miller saw his case suddenly taking form: Richard Bailey had Helen Brach killed because she was threatening to sue him over the horses she had purchased. It was, he realized, only a theory , but it was one he felt certain he could, in time, prove. Full of urgency, a man with a mission now that he had a hypothesis to guide him, he issued new orders to his troops: Find out everything you can about Richard Bailey and his crowd. Howard Blum, Vanity Fair , January 1995

And sometimes one term is used as a genus, or a means for defining the other:

Laplace's popular version of his astronomy, the Système du monde , was famous for introducing what came to be known as the nebular hypothesis , the theory that the solar system was formed by the condensation, through gradual cooling, of the gaseous atmosphere (the nebulae) surrounding the sun. Louis Menand, The Metaphysical Club , 2001 Researchers use this information to support the gateway drug theory — the hypothesis that using one intoxicating substance leads to future use of another. Jordy Byrd, The Pacific Northwest Inlander , 6 May 2015 Fox, the business and economics columnist for Time magazine, tells the story of the professors who enabled those abuses under the banner of the financial theory known as the efficient market hypothesis . Paul Krugman, The New York Times Book Review , 9 Aug. 2009

Incorrect Interpretations of "Theory"

Since this casual use does away with the distinctions upheld by the scientific community, hypothesis and theory are prone to being wrongly interpreted even when they are encountered in scientific contexts—or at least, contexts that allude to scientific study without making the critical distinction that scientists employ when weighing hypotheses and theories.

The most common occurrence is when theory is interpreted—and sometimes even gleefully seized upon—to mean something having less truth value than other scientific principles. (The word law applies to principles so firmly established that they are almost never questioned, such as the law of gravity.)

This mistake is one of projection: since we use theory in general use to mean something lightly speculated, then it's implied that scientists must be talking about the same level of uncertainty when they use theory to refer to their well-tested and reasoned principles.

The distinction has come to the forefront particularly on occasions when the content of science curricula in schools has been challenged—notably, when a school board in Georgia put stickers on textbooks stating that evolution was "a theory, not a fact, regarding the origin of living things." As Kenneth R. Miller, a cell biologist at Brown University, has said , a theory "doesn’t mean a hunch or a guess. A theory is a system of explanations that ties together a whole bunch of facts. It not only explains those facts, but predicts what you ought to find from other observations and experiments.”

While theories are never completely infallible, they form the basis of scientific reasoning because, as Miller said "to the best of our ability, we’ve tested them, and they’ve held up."

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Hypothesis vs. Theory

A hypothesis is either a suggested explanation for an observable phenomenon, or a reasoned prediction of a possible causal correlation among multiple phenomena. In science , a theory is a tested, well-substantiated, unifying explanation for a set of verified, proven factors. A theory is always backed by evidence; a hypothesis is only a suggested possible outcome, and is testable and falsifiable.

Comparison chart

Examples of theory and hypothesis.

Theory: Einstein's theory of relativity is a theory because it has been tested and verified innumerable times, with results consistently verifying Einstein's conclusion. However, simply because Einstein's conclusion has become a theory does not mean testing of this theory has stopped; all science is ongoing. See also the Big Bang theory , germ theory , and climate change .

Hypothesis: One might think that a prisoner who learns a work skill while in prison will be less likely to commit a crime when released. This is a hypothesis, an "educated guess." The scientific method can be used to test this hypothesis, to either prove it is false or prove that it warrants further study. (Note: Simply because a hypothesis is not found to be false does not mean it is true all or even most of the time. If it is consistently true after considerable time and research, it may be on its way to becoming a theory.)

This video further explains the difference between a theory and a hypothesis:

Common Misconception

People often tend to say "theory" when what they're actually talking about is a hypothesis. For instance, "Migraines are caused by drinking coffee after 2 p.m. — well, it's just a theory, not a rule."

This is actually a logically reasoned proposal based on an observation — say 2 instances of drinking coffee after 2 p.m. caused a migraine — but even if this were true, the migraine could have actually been caused by some other factors.

Because this observation is merely a reasoned possibility, it is testable and can be falsified — which makes it a hypothesis, not a theory.

• What is a Scientific Hypothesis? - LiveScience
• Wikipedia:Scientific theory

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Comments: Hypothesis vs Theory

Anonymous comments (2).

October 11, 2013, 1:11pm "In science, a theory is a well-substantiated, unifying explanation for a set of verified, proven hypotheses." But there's no such thing as "proven hypotheses". Hypotheses can be tested/falsified, they can't be "proven". That's just not how science works. Logical deductions based on axioms can be proven, but not scientific hypotheses. On top of that I find it somewhat strange to claim that a theory doesn't have to be testable, if it's built up from hypotheses, which DO have to be testable... — 80.✗.✗.139

May 6, 2014, 11:45pm "Evolution is a theory, not a fact, regarding the origin of living things." this statement is poorly formed because it implies that a thing is a theory until it gets proven and then it is somehow promoted to fact. this is just a misunderstanding of what the words mean, and of how science progresses generally. to say that a theory is inherently dubious because "it isn't a fact" is pretty much a meaningless statement. no expression which qualified as a mere fact could do a very good job of explaining the complicated process by which species have arisen on Earth over the last billion years. in fact, if you claimed that you could come up with such a single fact, now THAT would be dubious! everything we observe in nature supports the theory of evolution, and nothing we observe contradicts it. when you can say this about a theory, it's a pretty fair bet that the theory is correct. — 71.✗.✗.151

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• Key Differences

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Difference Between Hypothesis and Theory

The term ‘hypothesis’ is often contrasted with the term theory which implies an idea, typically proven, which aims at explaining facts and events. Both hypothesis and theory are important components of developing an approach, but these are not same. There exist a fine line of difference between hypothesis and theory, discussed in this article, have a look.

Content: Hypothesis Vs Theory

Comparison chart, definition of hypothesis.

An unproven statement or a mere assumption to be proved or disproved, about a factor, on which the researcher is interested, is called a hypothesis. It is a tentative statement, which is concerned with the relationship between two or more phenomena, as specified by the theoretical framework. The hypothesis has to go through a test, to determine its validity.

In other words, the hypothesis is a predictive statement, which can be objectively verified and tested through scientific methods, and relates the independent factor to the dependent one. To a researcher, a hypothesis is more like a question which he intends to resolve. The salient features of hypothesis are:

• It must be clear and precise or else the reliability of the inferences drawn will be questioned.
• It can be put to the test.
• If the hypothesis is relational, it should state the relationship between independent and dependent variables.
• The hypothesis should be open and responsive to testing within the stipulated time.
• It should be limited in scope and must be clearly defined.

Definition of Theory

An idea or a broad range of ideas that are assumed to be true, which aims at explaining cause and effect relationship between multiple observed phenomena. It is based on hypothesis, which after a thorough analysis and continuous testing and confirmation through observation and experiments, becomes a theory. As it is backed by evidence, it is scientifically proven.

Just like hypothesis, theories can also be accepted or rejected. As more and more information is gathered on the subject, theories are modified accordingly, to increase the accuracy of prediction over time.

Key Differences Between Hypothesis and Theory

The points given below are vital, so far as the difference between hypothesis and theory is concerned:

• Hypothesis refers to a supposition, based on few pieces of evidence, as an inception of further research or investigation. A theory is a well-affirmed explanation of natural phenomena, which is frequently validated through experimentation and observation.
• While the hypothesis is based on a little amount of data, the theory is based on a wide set of data.
• The hypothesis is an unproven statement; that can be tested. On the other hand, the theory is a scientifically tested and proven explanation of fact or event.
• Hypothesis relies on suggestions, prediction, possibility or projects whereas a theory is supported by evidence and is verified.
• The hypothesis may or may not be proved true, so the result is uncertain. On the contrary, the theory is one, that is assumed to be true and so its result is certain.
• Hypothesis and theory are two levels of the scientific method, i.e. theory follows hypothesis and the basis for research is hypothesis whose outcome is a theory.

Both hypothesis and theory are testable and falsifiable. When a hypothesis is proved true, by passing all critical tests and analysis, it becomes a theory. So, the hypothesis is very different from theory, as the former is something unproven but the latter is a proven and tested statement.

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BELLENS MOTEBEJANE says

July 15, 2019 at 2:31 pm

AMAIZING !WHAT ARE THE DIFFERENCE BETWEEN THEORY AND LAW?

February 17, 2022 at 3:47 am

Thanks, I’m finally clear on this for the first time in my life of 65 years

Curtis Le Gendre says

September 14, 2022 at 8:02 am

Great Information

Kenneth says

November 19, 2022 at 2:10 am

I was looking for some takes on this topic, and I found your article quite informative. It has given me a fresh perspective on the topic tackled. Thanks!

Stefanie Banis says

February 9, 2024 at 6:35 pm

Very informative! Thank you! I understand the difference much better now!

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Difference Between Hypothesis And Theory

Understanding the difference between a hypothesis and a theory is important in scientific research. A hypothesis is an educated guess or proposed explanation for a phenomenon, based on limited evidence and requiring further investigation. While, a theory is a well-substantiated explanation of an aspect of the natural world, supported by strong evidence and repeated testing. This distinction highlights the progression from initial inquiry to established scientific understanding.

Differentiate between Hypothesis and Theory

Table of Content

What is a Hypothesis?

Examples of hypothesis, what is theory, examples of theory, difference between hypothesis and theory, similarities between hypothesis and theory, conclusion: difference between hypothesis and theory.

A hypothesis is a scientific ‘what if ‘ statement. It is your guess or prediction about something you’re curious about. It is the starting point of the scientific investigation, it is a way to make an informed guess that you can test through experiments and observations. In other words, hypothesis is the first step in unraveling the mysteries of the world.

• Biology: Hypothesis: If I water this plant every day it will grow taller than the plant I water only once a week – this hypothesis explores the cause and effect relationship between watering and frequency and plant growth .
• Physics: Hypothesis: Increase the temperature of a gas cause it to expand – this hypothesis explores the behavior of gases under changing temperature conditions
• Psychology: Hypothesis: Increased access to education will decrease crime rate in community – This Hypothesis explores to understand the potential of human emotions

A theory is not a wild guess, it is a robust and thoroughly tested idea that explains a particular phenomenon. Theory is a combination of evidence, data and experiments. It contains good standard in scientific understanding and is well established.

• Biology: Theory of Evolution by Natural Selection : This Theory is proposed by Charles Darwin that explains how species change over time through the process of natural selection, here individuals with advantageous traits are more likely to survive and reproduce.
• Physics: Theory of General Relativity: Albert Einstein’s Theory explains that gravity works by explaining relationship between space, time and presence of mass which leads to bending of light by massive objects.
• Psychology: Cognitive Development Theory: Jean Piaget’s Theory explains stages of cognitive development in children, emphasizing how they acquire knowledge, problem solving, thinking skills etc.

The difference between Hypothesis and Theory is as follows:

Similarities between Hypothesis and Theory are given below:

• Scientific Basis: Both are fundamental components of the scientific method.
• Explanation of Phenomena: Aim to explain natural phenomena and provide understanding of the natural world.
• Subject to Testing: Can be tested through experiments and observations.
• Require Evidence: Both rely on evidence to be validated or supported.
• Falsifiable: Both must be falsifiable, meaning they can be disproven by evidence.
• Predictive Power: Make predictions that can be tested by further research.
• Foundation for Research: Both serve as foundations for scientific research and experimentation.
• Dynamic Nature: Can be refined or revised based on new evidence and findings.
• Communication Tools: Used to communicate scientific ideas and findings to the broader community.
• Guidance for Studies: Both provide direction for future studies and experiments.

In conclusion, while both hypotheses and theories are important to scientific inquiry, they differ significantly in their roles and stages. A hypothesis is an initial, testable proposition, while a theory is a well-substantiated explanation based on extensive evidence. Understanding these differences is essential for grasping the scientific method and the progression from questioning to comprehensive understanding.

Also Read: Hypothesis How to Write a Research Hypothesis- Step-By-Step Guide With Examples

FAQs on Difference Between Hypothesis And Theory

What is the main difference between a hypothesis and a theory in science.

A hypothesis is a guess based on limited evidence and theory is a well substantiated and comprehensive explanation that has extensive testing and research.

How do Hypotheses and Theories evolve in Science?

Hypotheses can evolve into theories when they are supported by a substantial evidence through repeated experiments and observations.

Can a Hypothesis become a Theory?

Yes, a hypothesis can develop into a theory when it contains significant evidence and is widely accepted within the scientific community. The process involves testing and validation.

Are Hypotheses less Important than Theories in Science?

No, both hypotheses and theories play crucial roles in scientific research. Hypotheses initiate investigations and guide experiments, theories provide a deep understanding of natural phenomena based on accumulated knowledge.

What Happens if a Hypothesis is not Supported by Evidence?

If a hypothesis is not supported by evidence from experiments or observations then it is either revised or rejected. This process of testing and modifying hypotheses is essential for scientific progress and accuracy.

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How to Write a Great Hypothesis

Hypothesis Definition, Format, Examples, and Tips

Kendra Cherry, MS, is a psychosocial rehabilitation specialist, psychology educator, and author of the "Everything Psychology Book."

Amy Morin, LCSW, is a psychotherapist and international bestselling author. Her books, including "13 Things Mentally Strong People Don't Do," have been translated into more than 40 languages. Her TEDx talk,  "The Secret of Becoming Mentally Strong," is one of the most viewed talks of all time.

Verywell / Alex Dos Diaz

• The Scientific Method

Hypothesis Format

Falsifiability of a hypothesis.

• Operationalization

Hypothesis Types

Hypotheses examples.

• Collecting Data

A hypothesis is a tentative statement about the relationship between two or more variables. It is a specific, testable prediction about what you expect to happen in a study. It is a preliminary answer to your question that helps guide the research process.

Consider a study designed to examine the relationship between sleep deprivation and test performance. The hypothesis might be: "This study is designed to assess the hypothesis that sleep-deprived people will perform worse on a test than individuals who are not sleep-deprived."

At a Glance

A hypothesis is crucial to scientific research because it offers a clear direction for what the researchers are looking to find. This allows them to design experiments to test their predictions and add to our scientific knowledge about the world. This article explores how a hypothesis is used in psychology research, how to write a good hypothesis, and the different types of hypotheses you might use.

The Hypothesis in the Scientific Method

In the scientific method , whether it involves research in psychology, biology, or some other area, a hypothesis represents what the researchers think will happen in an experiment. The scientific method involves the following steps:

• Forming a question
• Performing background research
• Creating a hypothesis
• Designing an experiment
• Collecting data
• Analyzing the results
• Drawing conclusions
• Communicating the results

The hypothesis is a prediction, but it involves more than a guess. Most of the time, the hypothesis begins with a question which is then explored through background research. At this point, researchers then begin to develop a testable hypothesis.

Unless you are creating an exploratory study, your hypothesis should always explain what you  expect  to happen.

In a study exploring the effects of a particular drug, the hypothesis might be that researchers expect the drug to have some type of effect on the symptoms of a specific illness. In psychology, the hypothesis might focus on how a certain aspect of the environment might influence a particular behavior.

Remember, a hypothesis does not have to be correct. While the hypothesis predicts what the researchers expect to see, the goal of the research is to determine whether this guess is right or wrong. When conducting an experiment, researchers might explore numerous factors to determine which ones might contribute to the ultimate outcome.

In many cases, researchers may find that the results of an experiment  do not  support the original hypothesis. When writing up these results, the researchers might suggest other options that should be explored in future studies.

In many cases, researchers might draw a hypothesis from a specific theory or build on previous research. For example, prior research has shown that stress can impact the immune system. So a researcher might hypothesize: "People with high-stress levels will be more likely to contract a common cold after being exposed to the virus than people who have low-stress levels."

In other instances, researchers might look at commonly held beliefs or folk wisdom. "Birds of a feather flock together" is one example of folk adage that a psychologist might try to investigate. The researcher might pose a specific hypothesis that "People tend to select romantic partners who are similar to them in interests and educational level."

Elements of a Good Hypothesis

So how do you write a good hypothesis? When trying to come up with a hypothesis for your research or experiments, ask yourself the following questions:

• Is your hypothesis based on your research on a topic?
• Can your hypothesis be tested?
• Does your hypothesis include independent and dependent variables?

Before you come up with a specific hypothesis, spend some time doing background research. Once you have completed a literature review, start thinking about potential questions you still have. Pay attention to the discussion section in the  journal articles you read . Many authors will suggest questions that still need to be explored.

How to Formulate a Good Hypothesis

To form a hypothesis, you should take these steps:

• Collect as many observations about a topic or problem as you can.
• Evaluate these observations and look for possible causes of the problem.
• Create a list of possible explanations that you might want to explore.
• After you have developed some possible hypotheses, think of ways that you could confirm or disprove each hypothesis through experimentation. This is known as falsifiability.

In the scientific method ,  falsifiability is an important part of any valid hypothesis. In order to test a claim scientifically, it must be possible that the claim could be proven false.

Students sometimes confuse the idea of falsifiability with the idea that it means that something is false, which is not the case. What falsifiability means is that  if  something was false, then it is possible to demonstrate that it is false.

One of the hallmarks of pseudoscience is that it makes claims that cannot be refuted or proven false.

The Importance of Operational Definitions

A variable is a factor or element that can be changed and manipulated in ways that are observable and measurable. However, the researcher must also define how the variable will be manipulated and measured in the study.

Operational definitions are specific definitions for all relevant factors in a study. This process helps make vague or ambiguous concepts detailed and measurable.

For example, a researcher might operationally define the variable " test anxiety " as the results of a self-report measure of anxiety experienced during an exam. A "study habits" variable might be defined by the amount of studying that actually occurs as measured by time.

These precise descriptions are important because many things can be measured in various ways. Clearly defining these variables and how they are measured helps ensure that other researchers can replicate your results.

Replicability

One of the basic principles of any type of scientific research is that the results must be replicable.

Replication means repeating an experiment in the same way to produce the same results. By clearly detailing the specifics of how the variables were measured and manipulated, other researchers can better understand the results and repeat the study if needed.

Some variables are more difficult than others to define. For example, how would you operationally define a variable such as aggression ? For obvious ethical reasons, researchers cannot create a situation in which a person behaves aggressively toward others.

To measure this variable, the researcher must devise a measurement that assesses aggressive behavior without harming others. The researcher might utilize a simulated task to measure aggressiveness in this situation.

Hypothesis Checklist

• Does your hypothesis focus on something that you can actually test?
• Does your hypothesis include both an independent and dependent variable?
• Can you manipulate the variables?
• Can your hypothesis be tested without violating ethical standards?

The hypothesis you use will depend on what you are investigating and hoping to find. Some of the main types of hypotheses that you might use include:

• Simple hypothesis : This type of hypothesis suggests there is a relationship between one independent variable and one dependent variable.
• Complex hypothesis : This type suggests a relationship between three or more variables, such as two independent and dependent variables.
• Null hypothesis : This hypothesis suggests no relationship exists between two or more variables.
• Alternative hypothesis : This hypothesis states the opposite of the null hypothesis.
• Statistical hypothesis : This hypothesis uses statistical analysis to evaluate a representative population sample and then generalizes the findings to the larger group.
• Logical hypothesis : This hypothesis assumes a relationship between variables without collecting data or evidence.

A hypothesis often follows a basic format of "If {this happens} then {this will happen}." One way to structure your hypothesis is to describe what will happen to the  dependent variable  if you change the  independent variable .

The basic format might be: "If {these changes are made to a certain independent variable}, then we will observe {a change in a specific dependent variable}."

A few examples of simple hypotheses:

• "Students who eat breakfast will perform better on a math exam than students who do not eat breakfast."
• "Students who experience test anxiety before an English exam will get lower scores than students who do not experience test anxiety."​
• "Motorists who talk on the phone while driving will be more likely to make errors on a driving course than those who do not talk on the phone."
• "Children who receive a new reading intervention will have higher reading scores than students who do not receive the intervention."

Examples of a complex hypothesis include:

• "People with high-sugar diets and sedentary activity levels are more likely to develop depression."
• "Younger people who are regularly exposed to green, outdoor areas have better subjective well-being than older adults who have limited exposure to green spaces."

Examples of a null hypothesis include:

• "There is no difference in anxiety levels between people who take St. John's wort supplements and those who do not."
• "There is no difference in scores on a memory recall task between children and adults."
• "There is no difference in aggression levels between children who play first-person shooter games and those who do not."

Examples of an alternative hypothesis:

• "People who take St. John's wort supplements will have less anxiety than those who do not."
• "Adults will perform better on a memory task than children."
• "Children who play first-person shooter games will show higher levels of aggression than children who do not." 

Collecting Data on Your Hypothesis

Once a researcher has formed a testable hypothesis, the next step is to select a research design and start collecting data. The research method depends largely on exactly what they are studying. There are two basic types of research methods: descriptive research and experimental research.

Descriptive Research Methods

Descriptive research such as  case studies ,  naturalistic observations , and surveys are often used when  conducting an experiment is difficult or impossible. These methods are best used to describe different aspects of a behavior or psychological phenomenon.

Once a researcher has collected data using descriptive methods, a  correlational study  can examine how the variables are related. This research method might be used to investigate a hypothesis that is difficult to test experimentally.

Experimental Research Methods

Experimental methods  are used to demonstrate causal relationships between variables. In an experiment, the researcher systematically manipulates a variable of interest (known as the independent variable) and measures the effect on another variable (known as the dependent variable).

Unlike correlational studies, which can only be used to determine if there is a relationship between two variables, experimental methods can be used to determine the actual nature of the relationship—whether changes in one variable actually  cause  another to change.

The hypothesis is a critical part of any scientific exploration. It represents what researchers expect to find in a study or experiment. In situations where the hypothesis is unsupported by the research, the research still has value. Such research helps us better understand how different aspects of the natural world relate to one another. It also helps us develop new hypotheses that can then be tested in the future.

Thompson WH, Skau S. On the scope of scientific hypotheses .  R Soc Open Sci . 2023;10(8):230607. doi:10.1098/rsos.230607

Taran S, Adhikari NKJ, Fan E. Falsifiability in medicine: what clinicians can learn from Karl Popper [published correction appears in Intensive Care Med. 2021 Jun 17;:].  Intensive Care Med . 2021;47(9):1054-1056. doi:10.1007/s00134-021-06432-z

Eyler AA. Research Methods for Public Health . 1st ed. Springer Publishing Company; 2020. doi:10.1891/9780826182067.0004

Nosek BA, Errington TM. What is replication ?  PLoS Biol . 2020;18(3):e3000691. doi:10.1371/journal.pbio.3000691

Aggarwal R, Ranganathan P. Study designs: Part 2 - Descriptive studies .  Perspect Clin Res . 2019;10(1):34-36. doi:10.4103/picr.PICR_154_18

Nevid J. Psychology: Concepts and Applications. Wadworth, 2013.

By Kendra Cherry, MSEd Kendra Cherry, MS, is a psychosocial rehabilitation specialist, psychology educator, and author of the "Everything Psychology Book."

Hypothesis vs. Theory — What's the Difference?

Difference Between Hypothesis and Theory

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Hypothesis vs. Theory: Understanding the Differences

“Hypothesis” and “theory” are two terms often used in science, but they have different meanings. Understanding the distinction between these two words can help us make sense of scientific explanations. In this article, we will explore the differences between “hypothesis” and “theory” in a way that is easy to understand. By the end, you’ll have a clearer grasp of these concepts and be able to use them confidently in scientific discussions.

Hypothesis vs. Theory

• A  hypothesis  is a preliminary assumption to be tested.
• A  theory  is a well-supported explanation for a broad range of phenomena.

Hypothesis vs. Theory: The Definition

What does hypothesis mean.

A hypothesis is a proposed explanation for a phenomenon or a scientific question that can be tested through experimentation or observation. It is an essential part of the scientific method, which involves formulating a hypothesis, conducting experiments to test it, and analyzing the results to draw conclusions.

In scientific research, a hypothesis serves as a tentative solution to a problem or a preliminary explanation for an observed phenomenon. It is based on existing knowledge and is formulated to be tested and potentially refuted through empirical evidence. A well-constructed hypothesis is specific, testable, and falsifiable, meaning that it can be proven false through experimentation or observation.

• Example of a hypothesis : “If a person consumes more vitamin C, then their immune system will be stronger and they will have a lower likelihood of catching a cold.”

What Does Theory Mean?

A theory is a well-substantiated explanation of some aspect of the natural world that is based on a body of evidence, observations, and experimentation. In the scientific context, a theory is more than just a guess or a hypothesis; it is a comprehensive framework that has been rigorously tested and supported by a substantial amount of empirical data.

Scientific theories are developed through the scientific method, which involves formulating hypotheses, conducting experiments, and analyzing the results. As evidence accumulates and supports a particular explanation, it may be elevated to the status of a theory. Importantly, scientific theories are not static or unchangeable; they are subject to modification or even rejection in light of new evidence or more comprehensive explanations.

• Example of a theory: The theory of evolution, which explains how species change over time through the process of natural selection.

Hypothesis vs. Theory: Usage

You employ  hypotheses  during the early stages of research to develop experiments. For instance, you might hypothesize that a plant given more sunlight will grow faster.

A  theory , like the Theory of Evolution, summarizes a group of tested hypotheses and facts to explain a complex set of patterns and behaviors.

For a better understanding of the differences between the two terms, let’s take a look at the table below:

Tips to Remember the Differences

• Think of a  hypothesis  as a  “hunch”  to be tested.
• View a  theory  as a  “tapestry”  of well-tested ideas.
• Use the phrase  “hypothesis for testing”  and  “theory for explaining”  to keep them distinct in your mind.

Hypothesis vs. Theory: Examples

Example sentences using hypothesis.

• She formulated a  hypothesis  to explain the observed pattern in the data.
• The researchers tested their  hypothesis  through a series of carefully controlled experiments.
• The  hypothesis  proposed by the scientist led to a new understanding of the chemical reaction.
• It is essential to develop a clear and testable  hypothesis  before conducting the research.
• The  hypothesis  was supported by the experimental results, providing valuable insights into the phenomenon.

Example Sentences Using Theory

• Einstein ‘s  theory of relativity has fundamentally altered our understanding of space and time.
• Darwin’s theory of natural selection provides a framework for understanding the evolution of species.
• The germ theory of disease is fundamental in developing medical hygiene practices.
• The  Big Bang theory is widely accepted as the leading explanation for the origin of the universe.
• The  kinetic molecular theory  explains the behavior of gases, including their volume and temperature relationships.

Related Confused Words

Hypothesis vs thesis.

A hypothesis is a specific, testable prediction that is proposed before conducting a research study, while a thesis is a statement or theory put forward to be maintained or proved. In essence, a hypothesis is a tentative assumption made in order to draw out and test its logical or empirical consequences, while a thesis is a proposition that is maintained by argument.

Both play distinct roles in the scientific and academic realms, with hypotheses guiding research and theses forming the central point of an argument or discussion.

Theory vs. Law

The primary difference between a scientific theory and a scientific law lies in their scope and function. A scientific theory is a well-substantiated explanation of some aspect of the natural world that is based on a body of evidence and has undergone rigorous testing and validation. In contrast, a scientific law describes a concise statement or mathematical equation that summarizes a wide variety of observations and experiments, often expressing a fundamental principle of nature.

While a theory provides an overarching framework for understanding a phenomenon, a law describes a specific, observable relationship. Both theory and law are vital components of scientific understanding, with theories offering explanations and laws providing concise descriptions of natural phenomena.

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Hypothesis vs. Theory: A Simple Guide to Tell Them Apart

By: Author ESLBUZZ

Posted on Last updated: July 27, 2023

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Hypothesis and theory are no stranger to those who conduct studies and work in science. These two terms are often used interchangeably by non-researchers, but they have distinct meanings in the scientific community. Understanding the difference between a hypothesis and a theory is essential for anyone interested in scientific research or critical thinking.

In this article, we will explore the differences between hypothesis and theory and provide examples to help you understand how they are used in scientific research. We will also discuss the importance of these terms in the scientific method and how they contribute to our understanding of the natural world. Whether you are a student, a researcher, or simply someone interested in science, this article will provide valuable insights into the world of scientific research.

To help illustrate the differences between hypothesis and theory, we will provide a comparison table that summarizes the key differences between these two terms and examples of how scientists use hypotheses and theories to explain natural phenomena and make predictions about future events. By the end of this article, you will have a clear understanding of the differences between hypothesis and theory and how they are used in scientific research.

Hypothesis vs. Theory

Hypothesis vs. Theory: Definitions

Understanding hypothesis.

A hypothesis is an educated guess or assumption that is made before conducting research. It is a tentative explanation for a phenomenon or observation that is based on limited evidence or prior knowledge. In other words, a hypothesis is a statement that proposes a relationship between two or more variables, which can be tested through further investigation.

Characteristics of Hypothesis

Hypotheses have certain characteristics that set them apart from other types of statements. These characteristics include:

• Testable: A hypothesis must be testable through empirical research. This means that it must be possible to collect data that can either support or refute the hypothesis.
• Specific: A hypothesis must be specific in its predictions. It should clearly state what is expected to happen and under what conditions.
• Falsifiable: A hypothesis must be falsifiable, which means that it must be possible to disprove the hypothesis if it is not supported by the evidence.
• Parsimonious: A hypothesis should be simple and straightforward. It should not include unnecessary assumptions or variables.

Examples of Hypothesis

Here are some examples of hypotheses:

• If a plant is exposed to sunlight, then it will grow faster than a plant that is not exposed to sunlight.
• If a person consumes more calories than they burn, then they will gain weight.
• If students are given more time to study for an exam, then they will perform better on the exam.

In summary, a hypothesis is an educated guess or assumption that is made before conducting research. It is testable, specific, falsifiable, and parsimonious. Examples of hypotheses include statements that propose a relationship between two or more variables, which can be tested through further investigation.

Understanding Theory

Definition of Theory

In scientific terms, a theory is a well-substantiated explanation of some aspect of the natural world that is based on empirical evidence. It is a collection of ideas that have been tested and confirmed through observation and experimentation. A theory is a framework that explains how and why things work in a certain way. It is a set of principles that can be used to make predictions about future events.

Characteristics of Theory

A theory has several characteristics that distinguish it from other scientific concepts such as hypotheses or laws. Some of the key characteristics of a theory are:

• A theory is based on empirical evidence and is supported by multiple lines of evidence.
• A theory is constantly evolving and can be modified or refined as new evidence emerges.
• A theory is generally accepted as true by the scientific community and is widely used to make predictions and guide research.
• A theory is not a guess or a hunch, but a well-substantiated explanation that has been rigorously tested.

Examples of Theory

There are many examples of well-established theories in science. Here are a few examples:

In summary, a theory is a well-substantiated explanation of some aspect of the natural world that is based on empirical evidence. It is a framework that explains how and why things work in a certain way and is constantly evolving as new evidence emerges. Theories are widely accepted as true by the scientific community and are used to make predictions and guide research.

Hypothesis vs. Theory: The Distinctions

As a writer, it is important to understand the differences between a hypothesis and a theory. These two scientific terms are often used interchangeably, but they have drastically different meanings in the world of science. In this section, we will explore the process of formulation, level of proof, and usage in the scientific community.

Process of Formulation

A hypothesis is an educated guess or assumption made before any research has been done. It is formed so that it can be tested to see if it might be true. Hypotheses are often based on observations or previous research and can be either proven or disproven through experimentation.

On the other hand, a theory is a well-established principle that is formed to explain the things already shown in data. Theories are based on a large body of evidence and have been extensively tested and proven through experimentation. The formulation of a theory requires a lot of research, experimentation, and analysis.

Level of Proof

The level of proof required for a hypothesis and a theory is vastly different. A hypothesis requires a certain level of proof to be considered valid, but it can still be disproven through experimentation. In contrast, a theory has been extensively tested and proven through experimentation, and therefore requires a much higher level of proof to be disproven.

Usage in Scientific Community

In the scientific community, hypotheses and theories play different roles. Hypotheses are used to generate predictions and testable explanations for phenomena, while theories are used to explain and predict a wide range of phenomena. Hypotheses are usually the starting point for research, while theories are the end result of extensive research and experimentation.

To summarize, a hypothesis is an educated guess or assumption made before any research has been done, while a theory is a well-established principle that is formed to explain the things already shown in data. Hypotheses require a certain level of proof to be considered valid, while theories require a much higher level of proof. In the scientific community, hypotheses are used to generate predictions and testable explanations for phenomena, while theories are used to explain and predict a wide range of phenomena.

Hypothesis vs. Theory: Common Misconceptions

When it comes to scientific research, there are several misconceptions about the differences between hypothesis and theory. In this section, we’ll explore some of the most common misconceptions and clarify the differences between these two scientific terms.

Misconception #1: Hypotheses are less important than theories

One common misconception is that hypotheses are less important than theories. This is not true. A hypothesis is the foundation of scientific research, as it is a proposed explanation for an observation or phenomenon. Without a hypothesis, there can be no scientific investigation.

Misconception #2: Hypotheses are guesses

Another common misconception is that hypotheses are guesses. While a hypothesis is an educated guess, it is not a random or arbitrary guess. A hypothesis is based on prior knowledge, observations, and data. It is a proposed explanation that can be tested through experimentation.

Misconception #3: Theories are proven facts

Many people believe that theories are proven facts. This is not true. A theory is a well-substantiated explanation for a set of observations or phenomena. It is based on a large body of evidence and has been repeatedly tested and confirmed through experimentation. However, theories are not absolute truths and are subject to revision or rejection based on new evidence.

Misconception #4: Hypotheses become theories

Some people believe that hypotheses become theories once they are proven. This is not true. A hypothesis can be supported or rejected by experimental evidence, but it does not become a theory. A theory is a broader explanation that encompasses many hypotheses and has been extensively tested and confirmed.

Misconception #5: Theories are more certain than hypotheses

Another common misconception is that theories are more certain than hypotheses. While theories are based on a large body of evidence and have been extensively tested, they are not absolute truths. Theories are subject to revision or rejection based on new evidence, just like hypotheses.

In summary, hypotheses and theories are both important components of scientific research. Hypotheses are proposed explanations that can be tested through experimentation, while theories are well-substantiated explanations that have been extensively tested and confirmed. While there are many misconceptions about the differences between hypotheses vs. theory, understanding these differences is crucial for conducting scientific research.

In conclusion, while the terms “hypothesis” and “theory” are often used interchangeably, they have distinct differences in the scientific method. A hypothesis is an assumption made before any research has been done, formed so that it can be tested to see if it might be true. On the other hand, a theory is a principle formed to explain the things already shown in data.

One way to differentiate between a hypothesis and a theory is to consider the level of evidence supporting each. A hypothesis is a proposed explanation for a phenomenon, but it is not yet supported by sufficient evidence. In contrast, a theory is a well-established explanation for a phenomenon that has been supported by a large body of evidence.

Another way to differentiate between a hypothesis and a theory is to consider their role in the scientific method. A hypothesis is an initial step in the scientific method, where a researcher formulates a testable prediction about a phenomenon. A theory, on the other hand, is the end result of the scientific method, where a researcher has tested and confirmed a hypothesis over time.

It is important to note that a hypothesis can eventually become a theory if it is repeatedly tested and supported by evidence. However, a theory can never become a hypothesis, as it is already a well-established explanation for a phenomenon.

In summary, understanding the differences between hypothesis and theory is crucial for conducting and interpreting scientific research. By using these terms correctly, researchers can communicate their ideas clearly and accurately, contributing to the advancement of scientific knowledge.

Frequently Asked Questions

How can you distinguish between hypothesis and theory?

A hypothesis is an educated guess or a proposed explanation for an observation or phenomenon. It is a tentative explanation that can be tested through experiments and observations. On the other hand, a theory is a well-established explanation that has been supported by a large body of evidence. The main difference between a hypothesis and a theory is that a hypothesis is a proposed explanation that needs to be tested, while a theory is a well-supported explanation that has been tested and confirmed by multiple lines of evidence.

What is the difference between a theory and a hypothesis in biology?

In biology, a hypothesis is a proposed explanation for a biological phenomenon that can be tested through experiments and observations. For example, a biologist might propose a hypothesis to explain why a particular species of bird has a particular beak shape. A theory in biology, on the other hand, is a well-established explanation that has been supported by a large body of evidence. For example, the theory of evolution is a well-established explanation for the diversity of life on Earth.

What is an example of a theory statement?

A theory statement is a statement that summarizes a well-established explanation for a phenomenon. For example, the theory of relativity is a statement that summarizes Einstein’s well-established explanation for the behavior of objects in space and time.

How are hypotheses and theories similar and different?

Both hypotheses and theories are proposed explanations for phenomena. However, while hypotheses are tentative and need to be tested, theories are well-established and have been supported by a large body of evidence. In addition, hypotheses are often specific to a particular observation or phenomenon, while theories are more general and can explain a wide range of phenomena.

What are some examples of the differences between a hypothesis and a theory?

An example of a hypothesis might be that a particular drug will cure a particular disease. An example of a theory might be the theory of plate tectonics, which explains the movement of the Earth’s crust. The main difference between these two examples is that the first is a tentative explanation that needs to be tested, while the second is a well-established explanation that has been supported by a large body of evidence.

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A theory statement is a statement that summarizes a well-established explanation for a phenomenon. For example, the theory of relativity is a statement that summarizes Einstein's well-established explanation for the behavior of objects in space and time.

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The best way to distinguish between hypotheses and theories is to remember that hypotheses are tentative explanations that need to be tested, while theories are well-established explanations that have been supported by a large body of evidence.

"}},{"@type":"Question","name":"What are some examples of the differences between a hypothesis and a theory?","acceptedAnswer":{"@type":"Answer","text":"

An example of a hypothesis might be that a particular drug will cure a particular disease. An example of a theory might be the theory of plate tectonics, which explains the movement of the Earth's crust. The main difference between these two examples is that the first is a tentative explanation that needs to be tested, while the second is a well-established explanation that has been supported by a large body of evidence.

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Scientific Hypothesis, Model, Theory, and Law

Understanding the Difference Between Basic Scientific Terms

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Words have precise meanings in science. For example, "theory," "law," and "hypothesis" don't all mean the same thing. Outside of science, you might say something is "just a theory," meaning it's a supposition that may or may not be true. In science, however, a theory is an explanation that generally is accepted to be true. Here's a closer look at these important, commonly misused terms.

A hypothesis is an educated guess, based on observation. It's a prediction of cause and effect. Usually, a hypothesis can be supported or refuted through experimentation or more observation. A hypothesis can be disproven but not proven to be true.

Example: If you see no difference in the cleaning ability of various laundry detergents, you might hypothesize that cleaning effectiveness is not affected by which detergent you use. This hypothesis can be disproven if you observe a stain is removed by one detergent and not another. On the other hand, you cannot prove the hypothesis. Even if you never see a difference in the cleanliness of your clothes after trying 1,000 detergents, there might be one more you haven't tried that could be different.

Scientists often construct models to help explain complex concepts. These can be physical models like a model volcano or atom  or conceptual models like predictive weather algorithms. A model doesn't contain all the details of the real deal, but it should include observations known to be valid.

Example: The  Bohr model shows electrons orbiting the atomic nucleus, much the same way as the way planets revolve around the sun. In reality, the movement of electrons is complicated but the model makes it clear that protons and neutrons form a nucleus and electrons tend to move around outside the nucleus.

A scientific theory summarizes a hypothesis or group of hypotheses that have been supported with repeated testing. A theory is valid as long as there is no evidence to dispute it. Therefore, theories can be disproven. Basically, if evidence accumulates to support a hypothesis, then the hypothesis can become accepted as a good explanation of a phenomenon. One definition of a theory is to say that it's an accepted hypothesis.

Example: It is known that on June 30, 1908, in Tunguska, Siberia, there was an explosion equivalent to the detonation of about 15 million tons of TNT. Many hypotheses have been proposed for what caused the explosion. It was theorized that the explosion was caused by a natural extraterrestrial phenomenon , and was not caused by man. Is this theory a fact? No. The event is a recorded fact. Is this theory, generally accepted to be true, based on evidence to-date? Yes. Can this theory be shown to be false and be discarded? Yes.

A scientific law generalizes a body of observations. At the time it's made, no exceptions have been found to a law. Scientific laws explain things but they do not describe them. One way to tell a law and a theory apart is to ask if the description gives you the means to explain "why." The word "law" is used less and less in science, as many laws are only true under limited circumstances.

Example: Consider Newton's Law of Gravity . Newton could use this law to predict the behavior of a dropped object but he couldn't explain why it happened.

As you can see, there is no "proof" or absolute "truth" in science. The closest we get are facts, which are indisputable observations. Note, however, if you define proof as arriving at a logical conclusion, based on the evidence, then there is "proof" in science. Some work under the definition that to prove something implies it can never be wrong, which is different. If you're asked to define the terms hypothesis, theory, and law, keep in mind the definitions of proof and of these words can vary slightly depending on the scientific discipline. What's important is to realize they don't all mean the same thing and cannot be used interchangeably.

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