EXCERPT Philosophy is a naturally sceptical discipline. Limits on what can be known, constant doubts about our most cherished beliefs, impossibility theorems – such is the gloomy lot of a philosopher. Fortunately for those of us with a more constructive outlook, not all philosophical results are so pessimistic. Were John Stuart Mill alive today, he may well have questioned our political wisdom, but he would surely be envious of the growth in our scientific epis-temology. Yet there is a group of constraints on knowledge that has seemed insurmountable. This group contains the egocentric predicament, the Ralph Barton Perry claim that each human can experience and know the world only from his or her individual psychological and perceptual perspective; its generalization, which we can call the anthropocentric predicament, the apparent fact that we can only experience and know the world from a specifically human perspective,one that is fixed in part by our peculiar evolutionary history; and the linguistic determinism position, the idea that the limits of language are the limits of thought. All of this pessimism is natural, most of it is well argued, and a great deal of it will be rendered irrelevant by developments in science. This essay will explain why…