Is there mustard in the refrigerator? Even the question of how you find the answer is not as simple as it seems, said Nicholas Silins, Cornell professor of philosophy, in an interview.
Answering questions of how we learn from perception requires knowing how we perceive the world in the first place, so Silins and Harvard University philosopher Susanna Siegel organized the Predictions and Motivations in Perception Conference to bring psychologists and philosophers together to learn from one another. The conference was held Sept. 11-12 at Cornell's A.D. White House.
"There's a lot of room for debate about the bearing of the psychological work on debates in epistemology," explained Silins. "If we see what we want to see in a given case, or what we antecedently expected in a given case, it's not obvious how we can learn from perception in that case. The psychological work also raises questions about whether, in certain cases, perception has the accuracy it might seem to need to give good evidence for belief."
"Philosophy and psychology weren't always seen as separate disciplines," pointed out Adam Bendorf, a graduate student studying philosophy. "George Berkeley did important psychological work, and so did Descartes and William James. And there are still philosophers today who are significant figures in cognitive science," such as Daniel Dennett and Patricia Churchland.
Participants in the conference examined such topics as how previous expectations, desires, physiology and racial stereotypes can influence perception. Shimon Edelman, professor of psychology, addressed the question of predictions in his lecture. "There is this increasingly widely accepted idea that minds have evolved because organisms of which they're a part need to look ahead and predict the future," he explained in an interview. Those predictions rest on Bayesian inference and decision-making, which use both prior experience and new data in a computational approach.
Edelman's lecture also addressed his recent research into the dynamics of representations of reality. "Experience is probably the most difficult thing to reason about and study scientifically," he said in an interview. "If we take as a premise that what's happening in your brain is all you are, what happens at a frozen point in time, when some neurons are firing and some are silent? What do the silent neurons contribute?" He characterized this question as philosophical, because it's driven by reasoning, not data. "The way out is to let time run its course and unfreeze the situation. This is an argument from first principles; if you don't postulate that you have a minimum duration of time, it's impossible to explain you as a physical person."
In another lecture, Emily Balcetis '06 described her research showing how desires and intentions can influence the processing of visual stimuli. Experiments she has done with David Dunning, professor of psychology, provide evidence that a desirable object (such as a gift card described as having a $25 value) looks closer than an undesirable object (such as a gift card described as having a $0 value) when the objects are actually placed equally far away from the subject.
"We're grateful for the patience of the psychologists in explaining their work," said Silins. "The conference was a great way to learn from psychologists, and to get their input into classic questions in epistemology." Bendorf added, "It clued me in to a large body of philosophically relevant psychological research that I didn't know about before."
Funding for the conference was provided by the Departments of Philosophy and Psychology and the Cognitive Science Program.
Linda Glaser is a staff writer for the College of Arts and Sciences.