essentially
different from it. Moreover, the acknowledgment of a certain group of gods
(the celestial bodies, for instance) combined with the rejection of
others, may create difficulties in defining the notion of atheism; in
practice, however, this doctrine generally coincides with the former, by
which the gods are explained away. On the whole it would hardly be just,
in a field of inquiry like the present, to expect or require absolutely
clearly defined boundary-lines; transition forms will always occur.

The persons of whom it is related that they denied the existence of the
ancient gods are in themselves few, and they all belong to the highest
level of culture; by far the greater part of them are simply professional
philosophers. Hence the inquiry will almost exclusively have to deal with
philosophers and philosophical schools and their doctrines; of religion as
exhibited in the masses, as a social factor, it will only treat by
exception. But in its purpose it is concerned with the history of
religion, not with philosophy; therefore--in accordance with the definition
of its object--it will deal as little as possible with the purely
philosophical notions of God that have nothing to do with popular
religion. What it aims at illustrating is a certain--if you like, the
negative--aspect of ancient religion. But its result, if it can be
sufficiently established, will not be without importance for the
understanding of the positive religious sense of antiquity. If you want to
obtain some idea of the hold a certain religion had on its adherents, it
is not amiss to know something about the extent to which it dominated even
the strata of society most exposed to influences that went against it.

It might seem more natural, in dealing with atheism in antiquity, to adopt
the definition current among the ancients themselves. That this method
would prove futile the following investigation will, I hope, make
sufficiently evident; antiquity succeeded as little as we moderns in
connecting any clear and unequivocal idea with the words that signify
"denial of God." On the other hand, it is, of course, impossible to begin
at all except from the traditions of antiquity about denial and deniers.
Hence the course of the inquiry will be, first to make clear what
antiquity understood by denial of the gods and what persons it designated
as deniers, and then to examine in how far these persons were atheists in
our sense of the word.