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A is A & The Law of Identity

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Today I was doing some research on "The Law of Identity" and I ran into a problem. When I was reviewing "Works of Aristotle" I could not find any mention of "The Law of Identity" nor could I find a specific outline of "A is A". As a result I began searching online to see if my book was missing something important. I found this link which claims that Aristotle never actually said any of it...not specifically anyway. Can someone point me in the right direction or shed some light on this for me?

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Isn't the law of identity implicit in the law of contradiction and the law of excluded middle?

I agree that it is implicit.

Contradiction is a word meaning "to be and not be, at the same time and in the same respect." This is the same as "A and not-A" or "A is not-A".

The metaphysical claim that contradictions do not exist negates the statement "A is not-A" into "A is not not-A", and the double negative on the last term cancels to "A is A".

I like this passage from the wikipedia entry on the Law of excluded middle

The Principle of Excluded Middle, along with its complement, the Law of Contradiction, are correlates of the Law of Identity; the first principle of thought (reason). Because the principle of identity intellectually partitions the Universe into exactly two parts: ‘self’ and ‘other, it creates a dichotomy wherein the two parts are ‘mutually exclusive’ and ‘jointly exhaustive’. The principle of contradiction is merely an expression of the mutually exclusive aspect of that dichotomy, and the principle of excluded middle is an expression of its jointly exhaustive aspect.
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Aristotle said that "a thing is itself" and demonstrated that this statement is an axiom, in Metaphysics (Book VII). That's the Law of Identity.

A is A (I believe Thomas Aquinas was the first to state the law of identity in this manner) means exactly the same thing, because A is meant as a placeholder for one (any one) existent: that's exactly the meaning of the concept "a thing".

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logicalpath :"When I was reviewing "Works of Aristotle" I could not find any mention of "The Law of Identity" nor could I find a specific outline of "A is A". "

No wonder.The Laws of Aristotle are 1. The Law of Contradiction.2. The Law of excluded Middle.

The Law of identity, A is A, had been formulated not by Aristotle but by philosopher Antonius Andreas in 12th century A.D. However, this Law obviously presents the same essential points of Aristotelian laws.

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