Legal skills and debates in Scotland
Legal skills and debates in Scotland

Start this free course now. Just create an account and sign in. Enrol and complete the course for a free statement of participation or digital badge if available.

1.2  Inductive reasoning and reasoning by analogy

1.2.1  Inductive reasoning

Inductive reasoning involves drawing a general conclusion from specific examples. When inductive reasoning takes place, the process is generally the reverse of deductive reasoning. It involves finding out the name of the wider category A of things that correctly describes all of the observable objects in that category. This can then be used to say something new about the specific case C that you are dealing with at the time. It is done by observing what you already know from a number of existing examples, collecting that knowledge together and forming a general rule about all of those examples that should also apply to other examples in the same category.

It is rarely possible, for example, to observe all possible instances of something. Therefore a general conclusion based on some specific instances that purports to account for all instances will not always or necessarily be true. It will only probably be true based on the available evidence. Look at this example, which might come up if you were wandering around ancient Greece:

Step 1

Observe examples:

This human Socrates is Greek.

And this human Plato is Greek.

And this human Euripides is Greek.

Step 2 (hidden step)Collect them together based on shared characteristics.
Step 3

Broader conclusion based on Step 2:

Therefore all humans (category B) are Greek (category A).

Step 4

Apply to specific case:

Therefore this other human Herodotus (case C) is also Greek (category A).

If you happen to see only Greek men, then you might logically but incorrectly conclude that all humans are Greek. (You might also incorrectly conclude that all humans are men.) The logical relationship between the statement categories is consequently less certain than with deductive reasoning, and is illustrated in Figure 3.

A process for inductive reasoning
Figure 3Inductive reasoning

In this example, as you have not been made aware of the existence of Barack Obama or Marie Curie from your experience, you have received incomplete information about the nationality of humans, which has resulted in a discrepancy in the general rule you have constructed from that information, that all humans are Greek. As Figure 3 illustrates, there is no necessary connection between those in the category of Greek humans and those in the broader category of humans. If you then use deductive reasoning to apply a flawed general principle derived from inductive reasoning to a specific case, you may end up with a statement about the case that is not true. It happened to be true that Herodotus was Greek, but if your case had been Marie Curie, this conclusion would not be true as she was French-Polish.

Inductive reasoning is not as rigorous as deductive reasoning in terms of its logical process. Instead, it is the process of building a hypothesis, a theory about a general rule, from the evidence available that both supports that theory and contradicts competing theories. The more evidence there is available, the higher the probability that the conclusion, the general rule, will be correct, but this can never be known for certain.

Take your learning further

Making the decision to study can be a big step, which is why you'll want a trusted University. The Open University has 50 years’ experience delivering flexible learning and 170,000 students are studying with us right now. Take a look at all Open University courses.

If you are new to University-level study, we offer two introductory routes to our qualifications. You could either choose to start with an Access module, or a module which allows you to count your previous learning towards an Open University qualification. Read our guide on Where to take your learning next for more information.

Not ready for formal University study? Then browse over 1000 free courses on OpenLearn and sign up to our newsletter to hear about new free courses as they are released.

Every year, thousands of students decide to study with The Open University. With over 120 qualifications, we’ve got the right course for you.

Request an Open University prospectus371