The parallel between Aenesidmus and Protagoras would become still more complete were it true that the Alexandrian philosopher also sought to base his Scepticism on the Heracleitean theory of Nature, arguing that contradictory assertions are necessitated by the presence of contradictory properties in every object.
ONE:It was natural that one who ranged with such consummate mastery over the whole world of apparent reality, should believe in no other reality; that for him truth should only319 mean the systematisation of sense and language, of opinion, and of thought. The visible order of nature was present to his imagination in such precise determination and fulness of detail that it resisted any attempt he might have made to conceive it under a different form. Each of his conclusions was supported by analogies from every other department of enquiry, because he carried the peculiar limitations of his thinking faculty with him wherever he turned, and unconsciously accommodated every subject to the framework which they imposed. The clearness of his ideas necessitated the use of sharply-drawn distinctions, which prevented the free play of generalisation and fruitful interchange of principles between the different sciences. And we shall have occasion to show hereafter, that, when he attempted to combine rival theories, it was done by placing them in juxtaposition rather than by mutual interpenetration. Again, with his vivid perceptions, it was impossible for him to believe in the justification of any method claiming to supersede, or even to supplement, their authority. Hence he was hardly less opposed to the atomism of Democritus than to the scepticism of Protagoras or the idealism of Plato. Hence, also, his dislike for all explanations which assumed that there were hidden processes at work below the surface of things, even taking surface in its most literal sense. Thus, in discussing the question why the sea is salt, he will not accept the theory that rivers dissolve out the salt from the strata through which they pass, and carry it down to the sea, because river-water tastes fresh; and propounds in its stead the utterly false hypothesis of a dry saline evaporation from the earths surface, which he supposes to be swept seawards by the wind.205 Even in his own especial province of natural history the same tendency leads him astray. He asserts that the spider throws off its web from the surface of its body like a skin, instead of evolving it from within, as Democritus had taught.206 The same thinker had320 endeavoured to prove by analogical reasoning that the invertebrate animals must have viscera, and that only their extreme minuteness prevents us from perceiving them; a view which his successor will not admit.207 In fact, wherever the line between the visible and the invisible is crossed, Aristotles powers are suddenly paralysed, as if by enchantment.
Machines do not create or consume, but only transmit and apply power; and it is only by conceiving of power as a constant element, independent of every kind of machinery, that the learner can reach a true understanding of the nature of machines. When once there is in the mind a fixed conception of power, dissociated from every kind of mechanism, there is laid, so to speak, a solid foundation on which an understanding of machines may be built up.The work to be performed consists in cutting away the metal between the teeth of a rack, leaving a perfect outline for the teeth; and as the shape of teeth cannot well be obtained by an adjustment of tools, it must be accomplished by the shape of the tools. The shape of the tools must, therefore, be constantly maintained, [155] and as the cross section of the displaced metal is not too great, it may be assumed that the shape of the tools should be a profile of the whole space between two teeth, and such a space be cut away at one setting or one operation. By the application of certain rules laid down in a former place in reference to cutting various kinds of material, reciprocating or planing tools may be chosen instead of rotary or milling tools.All right, Dick agreed cheerfully. But dont start in earning your nickname all over again, he warned.
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