identity


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Related to identity: identity crisis, personal identity

identity

a means of portraying arithmetically the enduring equality between two (or more) VARIABLES that are equal by definition. For example, £1 = 100p (or $1 = 100¢), and no matter how many pounds (or dollars) we have, they can always be converted into pennies (or cents) by multiplying by 100. Identities are generally given a three-bar ‘identity’ sign (=) to indicate that the value to the left of the three bars is identical to the value to the right of the sign. The QUANTITY THEORY OF MONEY is one of the best-known examples of an identity in economics, written as:

where M is the money stock, V is the velocity of circulation of money, P is the general price level and T is the number of transactions undertaken. See EQUATION.

References in classic literature ?
If the identity expresses organized rest, the counter action runs also into organization.
Wherever the impulse exceeds, the Rest or Identity insinuates its compensation.
The Arab garments aroused no doubt as to the man's identity, since he had trailed him into the Arab camp and out again, where he might easily have acquired the apparel.
Between the disasters that had befallen his master and his master's house, and the Frenchman, Mugambi saw a sinister relationship, which kept him from recalling to Werper's attention the identity which the latter evidently failed to recognize.
There could be no doubt of his sincerity nor any that he was cognizant of Gahan's identity.
On this view we can understand the relationship, with very little identity, between the productions of North America and Europe,--a relationship which is most remarkable, considering the distance of the two areas, and their separation by the Atlantic Ocean.
These cases of relationship, without identity, of the inhabitants of seas now disjoined, and likewise of the past and present inhabitants of the temperate lands of North America and Europe, are inexplicable on the theory of creation.
Vague identity, which is really close similarity, has been a source of many of the confusions by which philosophy has lived.
Vague words precede judgments of identity and difference; both general and particular words are subsequent to such judgments.
Moreover, I could see he now treated me as if I was myself beyond a doubt; so that first point of my identity seemed fully granted.
Does Miss Halcombe assert her supposed sister's identity to the owner of the Asylum, and take legal means for rescuing her?
Questions of identity, where instances of personal resemblance are concerned, are, in themselves, the hardest of all questions to settle--the hardest, even when they are free from the complications which beset the case we are now discussing.