Perplexities arise from the agreements ° between appearances or judgements, and these perplexities they distinguished under ten different modes in which the subjects in question appeared to vary. The following are the ten modes laid down. 6 The first mode relates to the differences between living creatures in respect of those things which give them pleasure or pain, or are useful or harmful to them. By this it is inferred that they do not receive the same impressions from the same things, with the result that such a conflict necessarily leads to suspension of judgement. For some creatures multiply without intercourse, for example, creatures that live in fire, the Arabian phoenix and worms ; others by union, such as man and the rest. Some are distinguished in one way, some in another, and for this reason they differ in their senses also, hawks for instance being most keen-sighted, and dogs having a most acute sense of smell. It is natural that if the senses, e.g. eyes, of animals differ, so also will the impressions produced upon them ; so to the goat vine-shoots are good to eat, to man they are bitter ; the quail thrives on hemlock, which is fatal to man ; the pig will eat ordure, the horse will not. The second mode has reference to the natures and idiosyncrasies of men; for instance, Demophon, Alexander's butler, used to get warm in the shade and shiver in the sun. Andron of Argos is reported by Aristotle to have travelled across the waterless deserts of Libya without drinking. Moreover, one man fancies the profession of medicine, another posed) consistency of our percepts or our concepts, were arranged bv them under ten modes." C£ Srvt Yix^J^yrrhJ.Iyp. i. §§ 36-163. %