Abstract
How veridical is perception? Rather than representing objects as they actually exist in the world, might perception instead represent objects only in terms of the utility they offer to an observer? Previous work employed evolutionary simulations to show that under certain assumptions, natural selection favors "strict interface" perceptual systems that represent objects exclusively in terms of subjective utility. These simulations showed that interface perceptual systems regularly drive "veridical" systems (those that represent objects in terms of their ground-truth, observer-independent properties) to extinction. This view has fueled considerable debate, but we think that discussions so far have failed to consider the implications of two critical aspects of perception. First, while previous simulations have explored single utility functions, perception must always serve multiple largely-independent goals. (Sometimes when looking at an apple you want to know how appropriate it is for eating, and other times you want to know how appropriate it is for throwing.) Second, perception often operates in an inflexible, automatic manner -- proving 'impenetrable' to shifting higher-level goals. (When your goal shifts from 'eating' to 'throwing', your visual experience does not dramatically transform.) These two points have important implications for the veridicality of perception. In particular, as the need for flexible goals increases, inflexible perceptual systems must become more veridical to meet that need. We support this position with evolutionary simulations showing that as the number of independent utility functions increases, the distinction between 'interface' and 'veridical' perceptual systems dissolves. Under one utility function (or one inflexible goal), our simulations replicate previous findings that favor interface systems, but under multiple independent utility functions, we find that veridical systems are best able to accommodate multiple goals. Although natural selection evaluates perceptual systems only in terms of fitness, the most fit perceptual systems may nevertheless represent the world as it is.