cter, men have established
of their own authority; as, for instance, the conduct of the father
of Gracchus, whom the Roman people made consul after his censorship,
because he had done nothing in his censorship without the knowledge of
his colleague.

But that is a decision admitting of comparisons, which in a multitude
of different circumstances contains some principle which is alike
in all. Its parts are three,--representation, collation, example. A
Representation is a statement demonstrating some resemblance of bodies
or natures; Collation is a statement comparing one thing with another,
because of their likeness to one another; Example is that which
confirms or invalidates a case by some authority, or by what has
happened to some man, or under some especial circumstances. Instances
of these things, and descriptions of them, will be given amid the
precepts for oratory. And the source of all confirmations has been
already explained as occasion offered, and has been demonstrated
no less clearly than the nature of the case required. But how each
separate statement, and each part of a statement, and every dispute
ought to be handled,--whether we refer to verbal discussion or
to writings,--and what arguments are suitable for each kind of
discussion, we will mention, speaking separately of each kind, in the
second book. At present we have only dropped hints about the numbers,
and moods, and parts of arguing in an irregular and promiscuous
manner; hereafter we will digest (making careful distinctions between
and selections from each kind of cause) what is suitable for each kind
of discussion, culling it out of this abundance which we have already
displayed.

And indeed every sort of argument can be discovered from among these
topics; and that, when discovered, it should be embellished, and
separated in certain divisions, is very agreeable, and highly
necessary, and is also a thing which has been greatly neglected by
writers on this art. Wherefore at this present time it is desirable
for us to speak of that sort of instruction, in order that perfection
of arguing may be added to the discovery of proper arguments. And all
this topic requires to be considered with great care and diligence,
because there is not only great usefulness in this matter, but there
is also extreme difficulty in giving precepts.

XXXI. All argumentation, therefore, is to be carried on either by
induction, or by ratiocination. Induction is a manner o