Logic and Theory of Knowledge 113
sense-perception, insofar as the criterion by which the truth of facts is
known is, generically, the presentation; and insofar as the account of
assent and the account of grasping and conception which is basic to other
accounts cannot be given without presentation. For the presentation is
first and then the intellect, which is verbally expressive, puts into rational
discourse what it experiences because of presentation.
- Presentation and phantasm are different. For a phantasm is a
semblance in the intellect of the sort which occurs in sleep and presenta-
tion is an impression in the soul, i.e., an alteration, as Chrysippus supposes
in book 2 of his On Soul. For one should not interpret "impression" as
[being like] the stamped outline made by a seal-ring, since it is impossible
for there to be many outlines in the same respect and on the same
substance. One conceives of a presentation which is from an existing
object and is moulded, outlined and stamped in accordance with the
existing object, such as could not come from a non-existing object.
- According to them, some presentations are sensible, some are non-
sensible. Those received through one or more sense organs are sensible;
non-sensible are those which come through the intellect, for example,
presentations of incorporeals and the other things grasped by reason. Of
sensible presentations, those which come from existing objects occur with
yielding and assent. But [representational] images^6 which are "as if" from
existing objects are also [counted] among the presentations. Again, of
presentations some are rational, some are non-rational. The presentations
of rational animals are rational, those of non-rational animals are non-
rational. The rational, then, are thoughts and the irrational have been
given no special name. And some presentations are technical, some non-
technical. For an image is considered differently by a technical specialist
and by a non-specialist.
- According to the Stoics, 'sense-perception' refers to [a] the pneuma
which extends from the leading part to the senses and [b] the "grasp"
which comes through the senses and [c] the equipment of the sense
organs (which some people may be impaired in). And [d] their activation
is also called sense-perception. According to them the grasp occurs [a]
through sense-perception (in the case of white objects, black objects,
rough objects, smooth objects); and [b] through reason (in the case of
conclusions drawn through demonstration, for example, that there are
gods and that they are provident). For of conceptions, some are conceived
on the basis of direct experience, some on the basis of similarity, some
on the basis of analogy, <some on the basis of transposition,> some on
the basis of composition and some on the basis of opposition.
- SeeM 7.169.