ar as we consider them as Kinds, it is enough to say:
_Whatever can be identified as a specimen of a known substance or Kind
has the properties of that Kind_. So far as we consider them as in the
relation of causation, we may say: _Whatever relation of events can be
identified with the relation of cause and effect is constant_. And these
principles may be generalised thus: _Whatever is constantly related to a
phenomenon (cause or Kind), determined by certain characters, is related
in the same way to any phenomenon, that has the same characters_. Taking
this as axiom of the syllogism materially treated, we see that
herbivorousness, being constantly related to ruminants, is constantly
related to camels; mortality to man and, therefore, to Socrates; rusting
to the immersion of iron in water generally and, therefore, to this
piece of iron. _Nota notae, nota rei ipsius_ is another statement of the
same principle; still another is Mill's axiom, "Whatever has a mark has
what it is a mark of." A mark is anything (A) that is never found
without something else (B)--a phenomenon constantly related to another
phenomenon--so that wherever A is found, B may be expected: human nature
is a mark of mortality.

Sec. 6. The Syllogism has sometimes been discarded by those who have only
seen that, as formally stated, it is either useless or fallacious: but
those who also perceive its material grounds retain and defend it. In
fact, great advantages are gained by stating an argument as a formal
syllogism. For, in the first place, we can then examine separately the
three conditions on which the validity of the argument depends:

(1) Are the Premises so connected that, _if they are true_, the
Conclusion follows? This depends upon the formal principles of chap. x.

(2) Is the Minor Premise true? This question can only arise when the
minor premise is a real proposition; and then it may be very difficult
to answer. Water rusts iron; but is the metal we are now dealing with a
fair specimen of iron? Few people, comparatively, know how to determine
whether diamonds, or even gold or silver coins, are genuine. That
_Camels are ruminants_ is now a verbal proposition to a Zoologist, but
not to the rest of us; and to the Zoologist the ascertaining of the
relation in which camels stand to such ruminants as oxen and deer, was
not a matter of analysing words but of dissecting specimens. What a long
controversy as to whether the human race constitutes a Fami