Читать книгу Introduction to Fuzzy Logic - James K. Peckol - Страница 49

The laws of thought are stipulated to be the rules by which rational discourse can be considered to be based. Thus, they are rules that apply, without exception, to any subject matter of thought. The three laws are as follows:

 The Law of Identity

 The Law of Excluded Middle

 The Law of Non‐contradiction

 Law of IdentityThe law of identity simply states that each entity or thing is identical to itself.

 Law of Non‐contradictionThe law of non‐contradiction is given by Aristotle. Among his other assertions, he contends that when trying to determine the nature of reality, the following principle applies. A substance cannot have a quality and yet simultaneously not have that same quality.

 Law of Excluded MiddleThe fundamental law of excluded middle, which originated with Plato, states that for any proposition, that proposition is either true or its negation is true.

Such a statement is an essential component of Boolean algebra and can be written as the classic exclusive OR: A = (M ∨ ~M). A is equal to M or not M. The symbol ∨ is OR and the symbol ~ is the term “not.”