Plausible reasoning

Then a person wearing a mask comes crawling out through the broken window, carrying a bag which turns out to be full of expensive jewellery.

For example, it might be that this person was the owner of the jewellery store and he was coming home from a fancy dress competition, and he didn't have the key with him.

But just as he walked by his store a passing truck threw a stone through the window; and he was only protecting his own property and not stealing the jewellery.

The evidence did not prove that the person was stealing jewellery, but it did make it extremely plausible.

During the fifth century B.C.E.,[2] judicial orators in Greek Sicily developed a method for successfully pleading their cases in such instances in which no eyewitnesses or written documents or other such direct evidence could be produced.

They began to base their arguments on the internal or external probability or plausibility of their statements.

Here is a classical example of argument by plausible reasoning presented by Aristotle in his Rhetoric: "If the accused is not open to the charge – for instance if a weakling be tried for violent assault – the defence is that he was not likely (eikós) to do such a thing.

The sophists, a sort of mendicant academicians were said to have been experts in this type of argumentation and they are said to have taught wealthy young Greeks these methods for a hefty fee.

Polya’s intention is to teach students the art of guessing new results in mathematics for which he marshals such notions as induction and analogy as possible sources for plausible reasoning.

The first volume of the book is devoted to an extensive discussion of these ideas with several examples drawn from various field of mathematics.

In the next chapter the techniques of generalization, specialization and analogy are presented as possible strategies for plausible reasoning.

In the remaining chapters, these ideas are illustrated by discussing the discovery of several results in various fields of mathematics like number theory, geometry, etc.

After a detailed analysis of several paradigmatic examples drawn from ancient Greek texts, D Walton and others formulated the following eleven properties as the defining characteristics of plausible reasoning.

[6] Allan M. Collins, a recognized authority on intelligent tutoring systems and plausible reasoning, presenting a core theory of the logic of plausible reasoning identified some of the important problems in the formulation of such a theory.

We need a computational scheme to calculate and compare different levels and strengths of belief.

It often happens that a plausible commonsense rule, when examined closely, has an almost unlimited number of possible types of exceptions.

Many useful commonsense concepts correspond to large systems of relations that are instantiated in many separate instances in the world.