The Law of Identity

From Logic

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Metaphysically, we can say that everything that exists has a specific nature. Each entity exists as something in particular and not it's own negation or antithesis.
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Metaphysically, we can say that everything that exists has a specific nature. Each entity exists as something in particular and it has characteristics that are a part of what it is. "This leaf is red, solid, dry, rough, and flammable." "This book is white, and has 312 pages." "This coin is round, dense, smooth, and has a picture on it." In all three of these cases we are referring to an entity with a specific identity; the particular type of identity, or the trait discussed, is not important. Their identities include all of their features, not just those mentioned.
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Existence necessitates identity: an entity without an identity is an oxymoron - to lack identity is to not possess any characteristics and to be a non existent. To exist is to exist as something, and that means to exist with a particular identity.
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Identity is the concept that refers to this aspect of existence; the aspect of existing as something in particular, with specific characteristics. An entity without an identity cannot exist because it would be nothing. To exist is to exist as something, and that means to exist with a particular identity.
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Each entity exists as something specific, its identity is particular, and it cannot exist as something else. An entity can have more than one characteristic, but any characteristic it has is a part of its identity. A car can be both blue and red, but not at the same time or not in the same respect. Whatever portion is blue cannot be red at the same time, in the same way. Half the car can be red, and the other half blue. But the whole car can't be both red and blue. These two traits, blue and red, each have single, particular identities.
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To have an identity means to have a single identity; an object cannot have two identities. A tree cannot be a telephone, and a dog cannot be a cat. Each entity exists as something specific, its identity is particular, and it cannot exist as something else. An entity can have more than one characteristic, but any characteristic it has is a part of its identity. A car can be both blue and red, but not at the same time or not in the same respect. Whatever portion is blue cannot be red at the same time, in the same way. Half the car can be red, and the other half blue. But the whole car can't be both red and blue. These two traits, blue and red, each have single, particular identities.
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The concept of identity is important because it makes explicit that reality has a definite nature. Since it exists in a particular way, it has characteristics. Since reality has an identity, it is knowable.  
The concept of identity is important because it makes explicit that reality has a definite nature. Since it exists in a particular way, it has characteristics. Since reality has an identity, it is knowable.  
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Finally, it is important to separate the logical law of identity from the metaphysical law: the universe exists and has an identity, but this in itself is not the 'law of identity', for the logical law to exist, a mind must glean it, [[a priori]].
==References==
==References==

Revision as of 22:28, 18 June 2007

Aristotle's Law of Identity Aristotle.gif

For propositions: "If a proposition is true, then it is true."

We can state this simply:

A=A

Or, in logical form:


Metaphysically, we can say that everything that exists has a specific nature. Each entity exists as something in particular and not it's own negation or antithesis.

Existence necessitates identity: an entity without an identity is an oxymoron - to lack identity is to not possess any characteristics and to be a non existent. To exist is to exist as something, and that means to exist with a particular identity.

Each entity exists as something specific, its identity is particular, and it cannot exist as something else. An entity can have more than one characteristic, but any characteristic it has is a part of its identity. A car can be both blue and red, but not at the same time or not in the same respect. Whatever portion is blue cannot be red at the same time, in the same way. Half the car can be red, and the other half blue. But the whole car can't be both red and blue. These two traits, blue and red, each have single, particular identities.

The concept of identity is important because it makes explicit that reality has a definite nature. Since it exists in a particular way, it has characteristics. Since reality has an identity, it is knowable.

Finally, it is important to separate the logical law of identity from the metaphysical law: the universe exists and has an identity, but this in itself is not the 'law of identity', for the logical law to exist, a mind must glean it, a priori.

References

  • Copi, I. M, Cohen, C., (2001), "Introduction to Logic", 11th Edition.
  • Landauer, J. & Rowlands J., (2001)
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