Phenomenal Indeterminacy and
the Bounds of Cognition
Brian Fiala
April 28th, 2007
University of Arizona
Overview
(1) Sense-datum theory & the speckled hen
(2) The argument from indeterminacy
(3) Generalizing the argument
(4) Resisting the argument
Overview
(1) Sense-datum theory & the speckled hen
(2) The argument from indeterminacy
(3) Generalizing the argument
(4) Resisting the argument
Sense-datum theory
 Acts of sensing involve a relation between a
subject and a mental object (a sense-datum).
 Sense-data exist only when sensed. There
are no unsensed sense-data.
 There is no appe arance/reality distinction
with respect to sense-data and their
properties.
The Problem of the Speckled Hen
Let us consider the visual
sense-datum which is yielded
by a single glance at a speckled
hen. The datum may be said to
“comprise” many speckles.
But what of the question of the
number of speckles? If we
judge that there are forty-eight,
it would seem, at first
consideration at least, that we
might very well best mistaken.
 Chisholm (1942)
The Speckled Hen (cont…)
 Chisholm is pointing out that there is no number n
of which one can say with complete certainty,
“My sense-datum comprises n speckles.”
 Judgments about sense-data are not basic
judgments (rather, they are inferential).
 Such judgments are fallible.
 Inferences about sense-data are defeasible.
Overview
(1) Sense-datum theory & the speckled hen
(2) The argument from indeterminacy
(3) Generalizing the argument
(4) Resisting the argument
Indeterminacy is in the head
 There is no indeterminacy in the world.
 Instead, indeterminacy is a feature of
representations of the world.
 Here I’ll suppose the above two theses.
 Not everyone will accept the suppositions.
 Still, many will accept the suppositions.
 Both are intuitively plausible.
Indeterminacy is in the head
 Our concepts mountain and foothill are
indeterminate with respect to some objects
 Yet the fundamental physical structure of
mountains and foothills is fully determinate
Phenomenal knowledge thesis PK
(PK) If a subject S is sensing a sense-datum
D, and if P is a phenomenal property,
then S is in a position to know whether
D determinately instantiates P.
Argument From Indeterminacy
(P1) If D is a sense-datum for S and D
determinately comprises 48 speckles, then S is in
a position to know that D comprises 48 speckles.
(P2) S is not in a position to know that D
determinately comprises 48 speckles.
(C1) It’s not the case that D determinately
comprises 48 speckles. (P1, P2, modus tollens)
Overview
(1) Sense-datum theory & the speckled hen
(2) The argument from indeterminacy
(3) Generalizing the argument
(4) Resisting the argument
Generalized PK thesis
(PK*) If a subject S undergoes a conscious
experience E, and if P is a phenomenal
property, then S is in a position to know
whether E determinately instantiates P.
Why is PK* an Attractive Thesis?
 Experience is immediate.
 Experience is self-presenting.
 There are no illusions with respect to the
properties of one’s experience. That is,
one can’t be mistaken about what it’s
like to have an experience (cf. Kripke on
“fool’s pain”).
HO-Representationalism and PK*
 Higher-order representationalism
 Conscious mental states (experiences) are states that the
subject is aware of. Consciousness entails awareness.
 A mental state M is a conscious experience iff there is a
mental state M* that (appropriately) represents M.
M*
M
HO-Representationalism and PK*
 We can individuate mental states such that
there is a 1-1 correspondence between
phenomenal properties and mental states
 HOTs are normally available for behavior
guidance (including rational behavior)
HO-Representationalism and PK*
Overview
(1) Sense-datum theory & the speckled hen
(2) The argument from indeterminacy
(3) Generalizing the argument
(4) Resisting the argument
Sperling’s ‘Matrix’ (1960)
T
I
V
F
X
L
S
E
B
A
W
T
Sperling Experiments
T
I
V
F
X
L
S
E
B
A
W
T
≈15-500ms
•
Tone:
•
Full report
Blank display
and
No mask
≈ 15-500ms
 High
 Medium
 Low
or
S reports letters
Sperling Experiments (cont…)
 “[T]he subjective image or sensation induced by the
light flash outlasts the physical stimulus at least until
the tone is heard. The stimulus information is thus
``stored’’ for a fraction of a second as a persisting
image…
 As the visual image fades, its legibility (information
content) decreases, and consequentially the
accuracy of reports based upon it decreases.”
• Sperling (1960: 20)
Rejecting PK*
 The information carried by an experience
may be highly determinate (and complex).
 But it takes time to extract that information.
 If the info is sufficiently complex (e.g. the
property 48-speckled-ness), the subject
may not have sufficient time to extract it.
 It doesn’t follow that the property was not
determinately present in the sensation.
THE END
 THE END
• THE END
 THE END
• THE END
 THE END