Assumption is an item that has no part in the scientific method of experimentation. In science, the definition of an assumption is an idea that is formed without evidence. An example of an everyday assumption is that there will be food at a party. Assumption is also defined as the act of taking on new responsibilities without being asked to do so. When used as a word, assumption is a noun related to the verb assume, and refers to the act of taking for granted or supposing something.

With a false assumption, it is called 'a 'false premise''. It is a kind of logic fallacy in which an underlying premise or proposition for an argument is false or invalid. When an argument uses a false assumption, the conclusion drawn from it may be false. This type of logical statement or conclusion is also known as syllogism.

Experts in many fields of science tell us that the scientific method of experimentation is a procedure with a purpose that has been characterized in natural science since the 17th century, consisting in systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses. Scientists are required to test hypotheses by conducting experiments and/or studies.

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