f
their victims_, the concepts _victim_, _murderer_, _ghost_ have a high
degree of congruity; yet, unfortunately, I cannot believe it: there
seems to be no such cheap defence of innocence. Now, Mill held that
Logic is concerned with the grounds of belief, and that the scope of
Logic includes Induction as well as Deduction; whereas, according to
Hamilton, Induction is only Modified Logic, a mere appendix to the
theory of the "forms of thought as thought." Indeed, Mill endeavoured in
his _Logic_ to probe the grounds of belief deeper than usual, and
introduced a good deal of Metaphysics--either too much or not
enough--concerning the ground of axioms. But, at any rate, his great
point was that belief, and therefore (for the most part) the Real
Proposition, is concerned not merely with the relations of words, or
even of ideas, but with matters of fact; that is, both propositions and
judgments point to something further, to the relations of things which
we can examine, not merely by thinking about them (comparing them in
thought), but by observing them with the united powers of thought and
perception. This is what convinces us that _water rusts iron_: and the
difficulty of doing this is what prevents our feeling sure that
_murderers are haunted by the ghosts of their victims_. Hence, although
Mill's definition of a proposition, given above, is adequate for
propositions in general; yet that kind of proposition (the Real) with
regard to which Logic (in Mill's view) investigates the conditions of
proof, may be more explicitly and pertinently defined as 'a predication
concerning the relation of matters of fact.'

Sec. 5. This leads to a very important distinction to which we shall often
have to refer in subsequent pages--namely, the distinction between the
Form and the Matter of a proposition or of an argument. The distinction
between Form and Matter, as it is ordinarily employed, is easily
understood. An apple growing in the orchard and a waxen apple on the
table may have the same shape or form, but they consist of different
materials; two real apples may have the same shape, but contain distinct
ounces of apple-stuff, so that after one is eaten the other remains to
be eaten. Similarly, tables may have the same shape, though one be made
of marble, another of oak, another of iron. The form is common to
several things, the matter is peculiar to each. Metaphysicians have
carried the distinction further: apples, they say, may have n