For men begin to doubt in questions of religion first, and then in
matters of more secular interest; and as regards the nature of the
spirit of historical criticism itself in its ultimate development,
it is not confined merely to the empirical method of ascertaining
whether an event happened or not, but is concerned also with the
investigation into the causes of events, the general relations
which phenomena of life hold to one another, and in its ultimate
development passes into the wider question of the philosophy of
history.

Now, while the workings of historical criticism in these two
spheres of sacred and uninspired history are essentially
manifestations of the same spirit, yet their methods are so
different, the canons of evidence so entirely separate, and the
motives in each case so unconnected, that it will be necessary for
a clear estimation of the progress of Greek thought, that we should
consider these two questions entirely apart from one another. I
shall then in both cases take the succession of writers in their
chronological order as representing the rational order - not that
the succession of time is always the succession of ideas, or that
dialectics moves ever in the straight line in which Hegel conceives
its advance. In Greek thought, as elsewhere, there are periods of
stagnation and apparent retrogression, yet their intellectual
development, not merely in the question of historical criticism,
but in their art, their poetry and their philosophy, seems so
essentially normal, so free from all disturbing external
influences, so peculiarly rational, that in following in the
footsteps of time we shall really be progressing in the order
sanctioned by reason.