The Department of Philosophy cordially invites you to the Public Defense of the PhD Dissertation
Cognitive Impenetrability Of Low-Level Perceptual Features
Members of the Defense Committee:
Supervisor: Katalin Farkas (CEU)
Examiner: Edouard Machery (University of Pittsburgh)
Examiner: Pierre Jacob (CEU & Institut Jean Nicod)
Chair: Michael Griffin (CEU)
Is our perception of the world influenced by what we believe or desire the world to be? The converse is surely true: we often come to believe and desire what we do on the basis of what we see, hear, touch, taste, and smell. Might perception be informed by cognition in a similarly specific and direct manner? In particular, might cognition influence perceptual experience in a way that sustains some semantic or logical or rational coherence between the source cognitive content and the resultant perceptual content, whereby this influence is not mediated by changes in the stimuli, the state of the sense organs, or the allocation of attention.
If the answer is yes, then perception is cognitively penetrable. Assumedly, this would have interesting theoretical implications regarding mental architecture (philosophy of mind and psychology), the justificatory role of perception (epistemology), and the theory-ladenness of observation (philosophy of science).
The central thesis of this dissertation is that, a trending view in philosophy and psychology to the contrary notwithstanding, there is in fact little reason to assume that perceptual experience of low-level features such as color or lightness is cognitively penetrable. It is not claimed outright that such an effect is empirically impossible. But it is argued that the prima facie best evidence and the arguments that build on them fall short of providing a convincing case for cognitive penetrability. So the burden is on defenders of the view to explain why anyone should still entertain that the posited kind of influence actually occurs.
Closely connected to the negative thesis regarding cognitive penetrability are two positive theses. One is that cognitively impenetrable perceptual processing is plausibly richer than is commonly assumed. It is argued in particular that intra-perceptual form-lightness associations and lightness contrast may explain away an apparent lexical effect that has been most widely proposed as a prime candidate of cognitive penetration.
The second positive thesis is that some of the best candidates of cognitive penetration may be better explained by changes in affect than by changes in perception or perceptual belief. It is argued in particular that even if the phenomenon of (hypnotically) suggested hallucination is not a sham, it still doesn’t follow that subjects experience genuine perceptual hallucination or cognitive delusion. More plausibly, just as suggested analgesia may involve a dissociation between the sensory and affective components of pain, it only feels to subjects as if the suggested perceptual state of affairs really pertained.
The dissertation thus defends cognitive impenetrability of perceptual experience while expanding on both the intra-perceptual and the extra-perceptual. The intra-perceptual account carries special weight insofar as it underscores the philosophical relevance of cognitively impenetrable perceptual processes. The importance of the extra-perceptual account is that it exposes as false a dichotomy according to which all candidate effects are either perceptually or cognitively mediated. Thus, in addition to the general conclusion that cognitive penetrability of perception is empirically implausible, a crucial implication of the dissertation is that the very dialectic of the cognitive-penetrability debate itself requires mending.