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TWO:Considered upon grounds of commercial expediency as a question of cost alone, it is generally cheaper to move material by hand when it can be easily lifted or moved by workmen, when the movement is mainly in a horizontal direction, and when the labour can be constantly employed; or, to assume a general rule which in practice amounts to much the same thing, vertical lifting should be done by motive power, and horizontal movement for short distances performed by hand. There is nothing more unnatural than for men to carry loads up stairs or ladders; the effort expended in such cases is one-half or more devoted to raising the weight of the body, which is not utilised in the descent, and it is always better to employ winding or other mechanism for raising weights, even when it is to be operated by manual labour. Speaking of this matter of carrying loads upward, I am reminded of the fact that builders in England and America, especially in the latter country, often have material carried up ladders, while in some of the older European countries, where there is but little pretension to scientific manipulation, bricks are usually tossed from one man to another standing on ladders at a distance of ten to fifteen feet apart.

TWO:According to Sir A. Grant, it is by the mystical and poetical side of his nature that Plato differs from Aristotle. The one ��aspired to a truth above the truth of scientific knowledge��; the other to ��methodised experience and the definite.��182 Now, setting aside the question whether there is any truth above the truth of scientific knowledge, we doubt very much whether Plato believed in its existence. He held that the most valuable truth was that which could be imparted to others by a process even more rigorous than mathematical reasoning; and there was no reality, however transcendent, that he did not hope to bring within the grasp of a dialectic without which even the meanest could not be understood. He did, indeed, believe that, so far, the best and wisest of mankind had owed much more to a divinely implanted instinct than to any conscious chain of reflection; but he distinctly293 asserted the inferiority of such guidance to the light of scientific knowledge, if this could be obtained, as he hoped that it could. On the other hand, Aristotle was probably superior to Plato as a poet; and in speaking about the highest realities he uses language which, though less rich and ornate than his master��s, is not inferior to it in force and fervour; while his metaphysical theories contain a large element of what would now be considered mysticism, that is, he often sees evidence of purpose and animation where they do not really exist. His advantage in definiteness is, of course, indisputable, but this was, perhaps, because he came after Plato and profited by his lessons.Lucretius dwells much on the dread of death as a source of vice and crime. He tells us that men plunge into all sorts of mad distractions or unscrupulous schemes of avarice and ambition in their anxiety to escape either from its haunting presence, or from the poverty and disrepute which they have learned to associate with it.181 Critics are disposed to think that the poet, in his anxiety to make a point, is putting a wrong interpretation on the facts. Yet it should be remembered that Lucretius was a profound observer, and that his teaching, in this respect, may be heard repeated from London pulpits at the present day. The truth seems to be, not that he went too far, but that he did not go far enough. What he decries as a spur to vicious energy is, in reality, a spur to all energy. Every passion, good or bad, is compressed and intensified by the contracting limits of mortality; and the thought of death impels men either to wring the last drop of enjoyment from their lives, or to take refuge from their perishing individualities in the relative endurance of collective enterprises and impersonal aims.