Gilbert Murray, The Rise of the Greek Epic
, 3rd ed. (Oxford: Clarendon Press, 1924), p. 5:
The classical books are in general the books which have possessed for mankind such vitality of interest that they are still read and enjoyed at a time when all the other books written within ten centuries of them have long since been dead. There must be something peculiar about a book of which the world feels after two thousand years that it has not yet had enough. One would like to know what it is that produces this permanent and not transient quality of interest. And it is partly for that that we study the Classics.