Deductive and inductive reasoning are both methods of reaching logically true conclusions used in scientific research as well as everyday life. Very often, they are confused. That is why a clear distinction between them should be made.
As defined by Anderson (2015), deductive reasoning, or deduction, is relevant to the conclusion that surely follows the assumption (p. 239). That means that the one using deduction assumes that what is true of a certain group of objects is also true about every single object from this group, i.e., reaching a logical conclusion starts with a general statement based on which the conclusion about observations is made.
In inductive reasoning, unlike deductive, the conclusion does not necessarily follow the assumptions (Anderson, 2015, p. 251), and using induction, the general statement is reached by using observations. That means that the conclusion is made after analyzing aspects of the problem, e.g., studying symptoms to make a diagnosis. The only problem with this method is that a particular set of observations does not always lead to the same general statement. Coming back to symptoms studied to make a diagnosis, the same set of symptoms may refer to different diseases.
To see the difference between the two, it may be useful to draw an example. Let us assume that Mary and Max are married, and Mindy is Mary’s daughter. One might conclude that Max is Mindy’s father, and Max is older than Mary. As for “Max is Mindy’s father,” it is a correct deductive inference, but “Max is older than Mary” may not be true, so it is a good inductive inference, but it may not be a correct deductive inference. So, deductive and inductive reasoning are both useful in reaching logical conclusions, but sometimes it might be difficult to define which method should be used to reach a conclusion that is true.
References
Anderson, J. R. (2015). Cognitive psychology and its implications (8th ed.). New York, NY: Worth Publishers.