he excess of
duration of the mental series over that of the body, is finite or
infinite.

Hume has discussed some of these questions in the remarkable essay _On
the Immortality of the Soul_, which was not published till after his
death, and which seems long to have remained but little known.
Nevertheless, indeed, possibly, for that reason, its influence has been
manifested in unexpected quarters, and its main arguments have been
adduced by archiepiscopal and episcopal authority in evidence of the
value of revelation. Dr. Whately,[36] sometime Archbishop of Dublin,
paraphrases Hume, though he forgets to cite him; and Bishop Courtenay's
elaborate work,[37] dedicated to the Archbishop, is a development of
that prelate's version of Hume's essay.

This little paper occupies only some ten pages, but it is not wonderful
that it attracted an acute logician like Whately, for it is a model of
clear and vigorous statement. The argument hardly admits of
condensation, so that I must let Hume speak for himself:--

"By the mere light of reason it seems difficult to prove the
immortality of the soul: the arguments for it are commonly derived
either from metaphysical topics, or moral, or physical. But in
reality it is the gospel, and the gospel alone, that has brought
_life and immortality_ to light.[38]

"1. Metaphysical topics suppose that the soul is immaterial, and
that 'tis impossible for thought to belong to a material
substance.[39] But just metaphysics teach us that the notion of
substance is wholly confused and imperfect; and that we have no
other idea of any substance, than as an aggregate of particular
qualities inhering in an unknown something. Matter, therefore, and
spirit, are at bottom equally unknown, and we cannot determine what
qualities inhere in the one or in the other.[40] They likewise
teach us, that nothing can be decided _a priori_ concerning any
cause or effect; and that experience, being the only source of our
judgments of this nature, we cannot know from any other principle,
whether matter, by its structure or arrangement, may not be the
cause of thought. Abstract reasonings cannot decide any question of
fact or existence. But admitting a spiritual substance to be
dispersed throughout the universe, like the ethereal fire of the
Stoics, and to be the only inherent subject of thought, we have
reason