fficient for belief, it must not only have a well-established fact (an
impression or memory-image) for its starting point, but, together with its
conclusion, it must keep within the limits of possible experience. The
limits of possible experience are also the limits of the knowable;
inferences to the continued existence of the soul after death and to the
being of God are vain sophistry and illusion. According to the famous
conclusion of the _Essay_, all volumes which contain anything other than
"abstract reasonings concerning quantity or number" or "experimental
reasonings concerning matter of fact and existence" deserve to be committed
to the flames. In view of this limitation of knowledge to that which is
capable of exact measurement and that which is present in experience, as
well of the principle that the elements added by thought are to be
sharply distinguished from the positively given (the immediate facts of
perception), we must agree with those who call Hume the father of modern
positivism.[2]

[Footnote 1: In the _Essay_, Hume describes his own standpoint as mitigated
or academical skepticism in antithesis to the Cartesian, which from doubt
and through doubt hopes to reach the indubitable, and to the excessive
skepticism of Pyrrhonism, which cripples the impulse to inquiry. This
moderate skepticism asks us only, after resisting the tendency to
unreflecting conclusions, to make a duty of deliberation and caution in
judging, and to restrain inquiry within those fields which are accessible
to our knowledge, _i.e._, the fields of mathematics and empirical fact. In
the _Treatise_ Hume had favored a sharper skepticism and extended his doubt
more widely, _e.g._, even to the trustworthiness of geometry. Cf. on this
point Ed. Grimm, _Zur Geschichte des Erkenntnissproblems_, 1890, p, 559
_seq_.]

[Footnote 2: So Volkelt, _Erfahrung und Denken_, 1886, p. 105.]

* * * * *

As a philosopher of religion Hume is the finisher and destroyer of deism.
Of the three principles of the deists--religion, its origin and its truth
are objects of scientific investigation; religion has its origin in the
reason and the consciousness of duty; natural religion is the oldest, the
positive religions are degenerate or revived forms of natural religion--he
accepts the first, while rejecting the other two. Religion may correspond
to reason or contradict it, but not proceed from it. Religion has its basis
in huma