Definition of a classic: a book everyone is assumed to have read and often thinks they have.

There are certain books in the world which every searcher for truth must know: the Bible, the Critique of Pure Reason, the Origin of Species, and Karl Marx's Capital.

A classic is a book that doesn't have to be written again.

A book is never a masterpiece: it becomes one. Genius is the talent of a dead man.

A classic is classic not because it conforms to certain structural rules, or fits certain definitions (of which its author had quite probably never heard). It is classic because of a certain eternal and irrepressible freshness.