Steven Pinker -- How the Mind Works - Hampshire High Italian ...

The Mind's Eye | 291this request: Visualize a lemon and a banana next to each other, but don'timagine the lemon either to the right or to the left, just next to thebanana. You will protest that the request is impossible; if the lemon andbanana are next to each other in an image, one or the other has to be onthe left. The contrast between a proposition and an array is stark. Propositionscan represent cats without grins, grins without cats, or any otherdisembodied abstraction: squares of no particular size, symmetry with noparticular shape, attachment with no particular place, and so on. That isthe beauty of a proposition: it is an austere statement of some abstractfact, uncluttered with irrelevant details. Spatial arrays, because they consistonly of filled and unfilled patches, commit one to a concrete arrangementof matter in space. And so do mental images: forming an image of"symmetry," without imagining a something or other that is symmetrical,can't be done.The concreteness of mental images allows them to be co-opted as ahandy analogue computer. Amy is richer than Abigail; Alicia is not asrich as Abigail; who's the richest? Many people solve these syllogismsby lining up the characters in a mental image from least rich to richest.Why should this work? The medium underlying imagery comeswith cells dedicated to each location, fixed in a two-dimensionalarrangement. That supplies many truths of geometry for free. Forexample, left-to-right arrangement in space is transitive: if A is to theleft of B, and B is to the left of C, then A is to the left of C. Anylookup mechanism that finds the locations of shapes in the array willautomatically respect transitivity; the architecture of the mediumleaves it no choice.Suppose the reasoning centers of the brain can get their hands on themechanisms that plop shapes into the array and that read their locationsout of it. Those reasoning demons can exploit the geometry of the arrayas a surrogate for keeping certain logical constraints in mind. Wealth,like location on a line, is transitive: if A is richer than B, and B is richerthan C, then A is richer than C. By using location in an image to symbolizewealth, the thinker takes advantage of the transitivity of location builtinto the array, and does not have to enter it into a chain of deductivesteps. The problem becomes a matter of plop down and look up. It is afine example of how the form of a mental representation determineswhat is easy or hard to think.Mental images also resemble arrays in shmooshing together size,shape, location, and orientation into one pattern of contours, rather