THREE:By examining into the facts, an apprentice will find that all truly successful establishments have been founded and built upon the mechanical abilities of some person or persons whose skill formed a base upon which the business was reared, and that true skill is the element which must in the end lead to permanent success. The material and the labour which make up the first cost of machines are, taking an average of various classes, nearly equally divided; labour being in excess for the finer class of machinery, and the material in excess for the coarser kinds of work. The material is presumed to be purchased at the same rates by those of inferior skill as by those that are well skilled, so that the difference in the first, or manufacturing cost of machinery, is determined mainly by skill.Returning to Epicurus, we have next to consider how he obtained the various motions required to bring his atoms into those infinite combinations of which our world is only the most recent. The conception of matter naturally endowed with capacities for moving in all directions indifferently was unknown to ancient physics, as was also that of mutual attraction and85 repulsion. Democritus supposed that the atoms all gravitated downward through infinite space, but with different velocities, so that the lighter were perpetually overtaken and driven upwards by the heavier, the result of these collisions and pressures being a vortex whence the world as we see it has proceeded.163 While the atomism of Democritus was, as a theory of matter, the greatest contribution ever made to physical science by pure speculation, as a theory of motion it was open to at least three insuperable objections. Passing over the difficulty of a perpetual movement through space in one direction only, there remained the self-contradictory assumption that an infinite number of atoms all moving together in that one direction could find any unoccupied space to fall into.164 Secondly, astronomical discoveries, establishing as they did the sphericity of the earth, had for ever disproved the crude theory that unsupported bodies fall downward in parallel straight lines. Even granting that the astronomers, in the absence of complete empirical verification, could not prove their whole contention, they could at any rate prove enough of it to destroy the notion of parallel descent; for the varying elevation of the pole-star demonstrated the curvature of the earths surface so far as it was accessible to observation, thus showing that, within the limits of experience, gravitation acted along convergent lines. Finally, Aristotle had pointed out that the observed differences in the velocity of falling bodies were due to the atmospheric resistance, and that, consequently, they would all move at the same rate in such an absolute vacuum as atomism assumed.165 Of these objections Epicurus ignored the first two, except, apparently, to the extent of refusing to believe in the antipodes. The third he acknowledged, and set himself to evade it by a hypothesis striking at the root of all scientific86 reasoning. The atoms, he tells us, suffer a slight deflection from the line of perpendicular descent, sufficient to bring them into collision with one another; and from this collision proceeds the variety of movement necessary to throw them into all sorts of accidental combinations. Our own free will, says Lucretius, furnishes an example of such a deflection whenever we swerve aside from the direction in which an original impulse is carrying us.166 That the irregularity thus introduced into Nature interfered with the law of universal causation was an additional recommendation of it in the eyes of Epicurus, who, as we have already mentioned, hated the physical necessity of the philosophers even more than he hated the watchful interfering providence of the theologians. But, apparently, neither he nor his disciples saw that in discarding the invariable sequence of phenomena, they annulled, to the same extent, the possibility of human foresight and adaptation of means to ends. There was no reason why the deflection, having once occurred, should not be repeated infinitely often, each time producing effects of incalculable extent. And a further inconsequence of the system is that it afterwards accounts for human choice by a mechanism which has nothing to do with free-will.167
FORE:Such, so far as they can be ascertained, are the most important facts in the life of Plotinus. Interwoven with these, we find some legendary details which vividly illustrate the superstition and credulity of the age. It is evident from his childish talk about the numbers six and nine that Porphyry was imbued with Pythagorean ideas. Accordingly, his whole account of Plotinus is dominated by the wish to represent that philosopher under the guise of a Pythagorean saint. We have already alluded to the manner in which he exalts his heros remarkable sagacity into a power of supernatural prescience and divination. He also tells us, with the most unsuspecting good faith, how a certain Alexandrian philosopher whose jealousy had been excited by the success of his illustrious countryman, endeavoured to draw down the malignant influences of the stars on the head of Plotinus, but was obliged to desist on finding that the attack recoiled on himself.421 On another occasion, an Egyptian priest, by way of exhibiting his skill in magic, offered to conjure up the daemon or guardian spirit of Plotinus. The latter readily consented, and the Temple of Isis was chosen for the scene of the operations, as, according to the Egyptian, no other spot sufficiently pure for the purpose could be found in Rome. The incantations were duly pronounced, when, much to the admiration of those present, a god made his appearance instead of the expected daemon. By what particular marks the divinity of the apparition was determined, Porphyry omits to mention. The philosopher was congratulated by his countryman on the possession of such a distinguished patron, but the celestial visitor vanished before any questions could be put to him. This mishap was attributed to a friend281 who, either from envy or fear, choked the birds which had been given him to hold, and which seem to have played a very important part in the incantation, though what it was, we do not find more particularly specified.422
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THREE:"Not from those people who advertise, Gordon?"
THREE:It seems hard to deprive engineering pursuits of the romance that is often attached to the business, and bring it down to a matter of commercial gain; but it is best to deal with facts, especially when such facts have an immediate bearing upon the general object in view. There is no intention in these remarks of disparaging the works of many noble men, who have given their means, their time, and sometimes their lives, to the advancement of the industrial arts, without hope or desire of any other reward than the satisfaction of having performed a duty; but we are dealing with facts, and no false colouring should prevent a learner from forming practical estimates of practical matters.
