We must therefore accept the view of the authorities followed by Cicero,
whether a thing is, that it is, and of
that kind it is. Nature herself imposes this upon us. For first
of all there must be some subject for the question, since we cannot
possibly determine what a thing is, or of what kind it is, until we have first
ascertained whether it is, and therefore the
first question raised is whether it is. But even
when it is clear that a thing is,
it is not immediately obvious what it is. And
when we have decided what it is, there remains the question of its quality. These three points once ascertained,
there is no further question to ask. These heads cover both definite and indefinite
questions. One or more of them is discussed in every
demonstrative, deliberative or forensic theme.
These heads again cover all cases in the courts, whether we regard them
from the point of view of rational or legal questions. For no legal problem can be
settled save by the aid of definition, quality
and conjecture.