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    Software name: appdown
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      In multiplying the variations of a measuring implement by mechanism, it is obvious that movable joints must be employed; it is also obvious that no positive joint, whether cylindrical or flat, could be so accurately fitted as to transmit such slight movement as occurs in gauging or measuring. This difficulty is in most measuring instruments overcome by employing a principle not before alluded to, but common in many machines, that of elastic [151] compensation.

      By classifying these processes, it will be seen that there is in all but a few functions to be performed by machines, and that they all act upon a few general principles. Engineering tools employed in fitting are, for example, all directed to the process of cutting. Planing machines, lathes, drilling machines, and shaping machines are all cutting machines, acting upon the same general planthat of a cleaving wedge propelled in straight or curved lines.There seem to be three principal points aimed at in the very ingenious theory which we have endeavoured to summarise as adequately as space would permit. Zeller apparently wishes to bring Socrates into line with the great tradition of early Greek thought, to distinguish him markedly from the Sophists, and to trace back to his initiative the intellectual method of Plato and Aristotle. We cannot admit that the threefold attempt has succeeded. It seems to us that a picture into which so much Platonic colouring has been thrown would for that reason alone, and without any further objection, be open to very grave suspicion. But even accepting the historical accuracy of everything that Plato has119 said, or of as much as may be required, our critics inferences are not justified by his authorities. Neither the Xenophontic nor the Platonic Socrates seeks knowledge for its own sake, nor does either of them offer a satisfactory definition of knowledge, or, indeed, any definition at all. Aristotle was the first to explain what science meant, and he did so, not by developing the Socratic notion, but by incorporating it with the other methods independently struck out by physical philosophy. What would science be without the study of causation? and was not this ostentatiously neglected by the founder of conceptualism? Again, Plato, in the Theaettus, makes his Socrates criticise various theories of knowledge, but does not even hint that the critic had himself a better theory than any of them in reserve. The author of the Phaedo and the Republic was less interested in reforming the methods of scientific investigation than in directing research towards that which he believed to be alone worth knowing, the eternal ideas which underlie phenomena. The historical Socrates had no suspicion of transcendental realities; but he thought that a knowledge of physics was unattainable, and would be worthless if attained. By knowledge he meant art rather than science, and his method of defining was intended not for the latter but for the former. Those, he said, who can clearly express what they want to do are best secured against failure, and best able to communicate their skill to others. He made out that the various virtues were different kinds of knowledge, not from any extraordinary opinion of its preciousness, but because he thought that knowledge was the variable element in volition and that everything else was constant. Zeller dwells strongly on the Socratic identification of cognition with conduct; but how could anyone who fell at the first step into such a confusion of ideas be fitted either to explain what science meant or to come forward as the reformer of its methods? Nor is it correct to say that Socrates approached an object from every point of view, and took note of all its characteristic qualities. On the contrary, one would120 be inclined to charge him with the opposite tendency, with fixing his gaze too exclusively on some one quality, that to him, as a teacher, was the most interesting. His identification of virtue with knowledge is an excellent instance of this habit. So also is his identification of beauty with serviceableness, and his general disposition to judge of everything by a rather narrow standard of utility. On the other hand, Greek physical speculation would have gained nothing by a minute attention to definitions, and most probably would have been mischievously hampered by it. Aristotle, at any rate, prefers the method of Democritus to the method of Plato; and Aristotle himself is much nearer the truth when he follows on the Ionian or Sicilian track than when he attempts to define what in the then existing state of knowledge could not be satisfactorily defined. To talk about the various elementsearth, air, fire, and wateras things with which everybody was already familiar, may have been a crude unscientific procedure; to analyse them into different combinations of the hot and the cold, the light and the heavy, the dry and the moist, was not only erroneous but fatally misleading; it was arresting enquiry, and doing precisely what the Sophists had been accused of doing, that is, substituting the conceit for the reality of wisdom. It was, no doubt, necessary that mathematical terms should be defined; but where are we told that geometricians had to learn this truth from Socrates? The sciences of quantity, which could hardly have advanced a step without the help of exact conceptions, were successfully cultivated before he was born, and his influence was used to discourage rather than to promote their accurate study. With regard to the comprehensive all-sided examination of objects on which Zeller lays so much stress, and which he seems to regard as something peculiar to the conceptual method, it had unquestionably been neglected by Parmenides and Heracleitus; but had not the deficiency been already made good by their immediate successors? What else is the121 philosophy of Empedocles, the Atomists, and Anaxagoras, but an attemptwe must add, a by no means unsuccessful attemptto recombine the opposing aspects of Nature which had been too exclusively insisted on at Ephesus and Elea? Again, to say that the Sophists had destroyed physical speculation by setting these partial aspects of truth against one another is, in our opinion, equally erroneous. First of all, Zeller here falls into the old mistake, long ago corrected by Grote, of treating the class in question as if they all held similar views. We have shown in the preceding chapter, if indeed it required to be shown, that the Sophists were divided into two principal schools, of which one was devoted to the cultivation of physics. Protagoras and Gorgias were the only sceptics; and it was not by setting one theory against another, but by working out a single theory to its last consequences, that their scepticism was reached; with no more effect, be it observed, than was exercised by Pyrrho on the science of his day. For the two great thinkers, with the aid of whose conclusions it was attempted to discredit objective reality, were already left far behind at the close of the fifth century; and neither their reasonings nor reasonings based on theirs, could exercise much influence on a generation which had Anaxagoras on Nature and the encyclopaedia of Democritus in its hands. There was, however, one critic who really did what the Sophists are charged with doing; who derided and denounced physical science on the ground that its professors were hopelessly at issue with one another; and this critic was no other than Socrates himself. He maintained, on purely popular and superficial grounds, the same sceptical attitude to which Protagoras gave at least the semblance of a psychological justification. And he wished that attention should be concentrated on the very subjects which Protagoras undertook to teachnamely, ethics, politics, and dialectics. Once more, to say that Socrates was conscious of not coming up to his own122 standard of true knowledge is inconsistent with Xenophons account, where he is represented as quite ready to answer every question put to him, and to offer a definition of everything that he considered worth defining. His scepticism, if it ever existed, was as artificial and short-lived as the scepticism of Descartes.

      That mad fury was also intensified considerably by the accusations about gruesome mutilations committed on German soldiers by Belgians, who were said to have cut off the noses, ears, genitals, and so on of their enemies. These rumours were so persistent that in the end it was generally believed in neutral countries that these things had happened frequently.

      "My name, sir," said the other coolly and clearly, "is Mr. Garrett Charlton, the owner of this house. And who are you?"

      The relation of Spinozas Substance to its attributes is ambiguous. It is at once their cause, their totality, and their unity. The highly elastic and indefinite term Power helped these various aspects to play into and replace one another according to the requirements of the system. It is associated with the subjective possibility of multiplying imaginary existences to any amount; with the causal energy in which existence originates; and with the expansiveness characteristic alike of Extension and of Thought. For the two known attributes of the universal substance are not simply related to it as co-predicates of a common subject; they severally express its essential Power, and are, to that extent, identical with one another. But when we ask, How do they express Power? the same ambiguity recurs. Substance is revealed through its attributes, as a cause through its effects; as an aggregate through its constituents; and as an abstract notion through its concrete embodiments. Thus Extension and Thought are identical through their very differences, since these illustrate the versatility of their common source, and at the same time jointly contribute to the realisation of its perfection. But, for all practical purposes, Spinoza deals only with the parallelism and resemblance of the attributes. We have to see how he establishes it, and how far he was helped in so doing by the traditions of Greek philosophy.

      According to Aristotle, the Heracleitean flux was inconsistent with the highest law of thought, and made all predication impossible. It has been shown that the master himself recognised a fixed recurring order of change which could be affirmed if nothing else could. But the principle of change, once admitted, seemed to act like a corrosive solvent, too powerful for any vessel to contain. Disciples were soon found who pushed it to extreme consequences with the effect of abolishing all certainty whatever. In Platos time it was impossible to argue with a Heracleitean; he could never be tied down to a definite statement. Every proposition became false as soon as it was uttered, or rather before it was out of the speakers mouth. At last, a distinguished teacher of the school declined to commit himself by using words, and disputed exclusively in dumb show. A dangerous speculative crisis had set in. At either extremity of the Hellenic world the path of scientific inquiry was barred; on the one hand by a theory eliminating non-existence from thought, and on the other hand by a theory identifying it with existence. The26 luminous beam of reflection had been polarised into two divergent rays, each light where the other was dark and dark where the other was light, each denying what the other asserted and asserting what the other denied. For a century physical speculation had taught that the universe was formed by the modification of a single eternal substance, whatever that substance might be. By the end of that period, all becoming was absorbed into being at Elea, and all being into becoming at Ephesus. Each view contained a portion of the truth, and one which perhaps would never have been clearly perceived if it had not been brought into exclusive prominence. But further progress was impossible until the two half-truths had been recombined. We may compare Parmenides and Heracleitus to two lofty and precipitous peaks on either side of an Alpine pass. Each commands a wide prospect, interrupted only on the side of its opposite neighbour. And the fertilising stream of European thought originates with neither of them singly, but has its source midway between.


      "No, sir, I am returning from there."




      In conclusion, I will say on the subject of patterns and castings, that a learner must depend mainly upon what he can see and what is explained to him in the pattern-shop and foundry. He need never fear an uncivil answer to a proper question, applied at the right time and place. Mechanics who have enough knowledge to give useful information of their business, have invariably the courtesy and good sense to impart such information to those who require it.