One of the main characteristics of scientific methodology is verification and falsification. Remember J. 4 that an appeal is made to Dieun if we conclude for lack of evidence that something is the case or not. While there are times when a lack of evidence should lead to a judgment that the original claim is not substantiated (as in a criminal court), this is not the case in scientific practices. Under the tailings method, if we have a number of factors that are assumed to be the causes of a number of effects, and we have reason to believe that all factors, with the exception of a factor C, are causes of all effects, with the exception of one, we should infer that C is the cause of the residual effect. The method of accompanying variation says that if, in a number of situations that lead to a particular effect, we find some ownership of the effect that varies with variation in a factor common to these situations, then we can infer that factor as a cause. This situation is an example of Mills` common method of agreement and difference: the first four students are proof that all those who got sick had eaten coleslaw, and the four matching couples are proof that only those who fell ill had eaten coleslaw. This is a strong combination of the first two methods, as it tends to support our idea that real causes are necessary and that the conditions for their effects are sufficient. It is important to remember that the use of the scientific method attempts to confirm or disprove a hypothesis; However, this process must always be considered partial and temporary. The weight we give to a confirmation or rebuttal is never all or nothing. We need to gather evidence over a long period of time. If we make mistakes, they are revealed by the results of repeated experiments.
Precisely determining the causes and effects is not an easy task. We can often confuse or misrepreseg the two because we lack sufficient information. Mill`s methods are attempts to isolate a cause from a complex sequence of events. Even simply referred to as the “common method,” this principle represents only the application of methods of concordance and difference. Symbolically, the common method of agreement and difference can be presented as: Mills rule of agreement states that if, in all cases where an effect occurs, there is a pre-C factor common to all these cases, then C is the cause of the effect. According to the table in this example, the only thing you ate was oysters. Therefore, if we apply the rule of concordance, we conclude that the consumption of oysters is the cause of the disease. Symbolically, the method of accompanying variation can be presented as (with ± a change): the philosopher John Stuart Mill has developed a series of five methods (or canons) that analyze and interpret our observations in order to draw conclusions about the causal relationships they have shown. Mills` methods are five methods of induction described by the philosopher John Stuart Mill in 1843 in his book A System of Logic.  They must shed light on issues of causation. To see how each of the five methods works, we look at their practical application to a particular situation.
Suppose an otherwise uneventful afternoon, the university nurse realizes that an unusual number of students suffer from severe digestive disorders. Of course, Ms. Hayes suspects that this symptom is due to something that the students ate for lunch, and I`m sure she wants to find out. The nurse wants to find evidence that supports a conclusion that “eat?xxxx? causes digestive problems. Mill methods can help. The common method deals with both the method of agreement and the method of difference as indicated by the diagram above.