318 ///-31 to ///-32
discussing. For if they say that in their argument grasping is assenting
to a graspable presentation (a graspable presentation being one which
comes from an existing thing and is stamped and moulded in accordance
with the existing object, and is such that it could not have come from a
non-existing object) then they themselves will probably not want to [say
that] they cannot investigate things which they have not grasped in this
sense. 5. Thus, for example, when a Stoic makes a critical investigation
of the Epicurean who says that substance is divided or that god does not
exercise providence over things which happen in the cosmos or that
pleasure is a good thing, has [the Stoic] then grasped [these things] or
not? And if he has, then by saying that they exist he has utterly abolished
Stoicism; but if he has not grasped them, then he is not able to say
anything against them.
- One should make a similar reply to the followers of other systems,
when they want to investigate one of the doctrines of those who hold
different views. Consequently, they cannot make critical investigations
of each other. Or rather, to avoid babbling, virtually their entire dogmatic
philosophy will be thrown into confusion and sceptical philosophy will
be vigorously promoted if it is granted that one cannot investigate what
is not grasped in this sense. 7. For he who makes a pronouncement and
dogmatizes about some non-evident thing either will say that he makes
this pronouncement about it after grasping it or after not grasping it. If
he does so after not grasping it, he will be untrustworthy. But if he does
so after grasping it, either he will say that he grasped it because it struck
him immediately, in its own right, and as a clear fact, or that he did so
by means of a kind of search and investigation. 8. But if the non-evident
thing is said to have occurred to him in its own right and as a clear fact
and that [that is why] it was grasped, in that case it wouldn't even be
non-evident but would be equally apparent to all and agreed upon and
not a matter of disagreement. But each of the non-evident things has
been the subject of an interminable disagreement among the dogmatists;
therefore the dogmatist who commits himself to the existence of and
pronounces about the non-evident thing would not have grasped it be-
cause it occurred to him in its own right and evidently. 9. But if he does
so by means of a kind of search, how (on the present hypothesis) will
he be able to investigate it before he grasps it with precision? For since
the investigation requires a prior precise grasp of what is to be investigated
and investigated in this way, and the grasp of the subject being investi-
gated again itself demands that there should have been an exhaustive
prior investigation of this subject, then by the circular mode for producing
doubt, the investigation of non-evident things and dogmatizing about
them will become impossible for them; if some people want to take the
grasping as their starting point, we bring them to see that it must be