And as for damnation, surely the Creator of so vast a universe had something better to think about than sending men to hell for minute theological errors. Judas Iscariot might be damned, but not Newton, though he were an Arian.
There were of course many other reasons for self-satisfaction. The Tartars had been confined to Asia, and the Turks were ceasing to be a menace. Comets had been humbled by Halley, and as for earthquakes, though they were still formidable, they were so interesting that men of science could hardly regret them. Western Europeans were growing rapidly richer, and were becoming lords of all the world: they had conquered North and South America, they were powerful in Africa and India, respected in China and feared in Japan. When to all this were added the triumphs of science, it is no wonder that the men of the seventeenth century felt themselves to be fine
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fellows, not the miserable sinners that they still proclaimed themselves on Sundays.
There are some respects in which the concepts of modern theoretical physics differ from those of the Newtonian system. To begin with, the conception of “force,” which is prominent in the seventeenth century, has been found to be superfluous. “Force,” in Newton, is the cause of change of motion, whether in magnitude or direction. The notion of cause is regarded as important, and force is conceived imaginatively as the sort of thing that we experience when we push or pull. For this reason it was considered an objection to gravitation that it acted at a distance, and Newton himself conceded that there must be some medium by which it was transmitted. Gradually it was found that all the equations could be written down without bringing in forces. What was observable was a certain relation between acceleration and configuration; to say that this relation was brought about by the intermediacy of “force” was to add nothing to our knowledge. Observation shows that planets have at all times an acceleration towards the sun, which varies inversely as the square of their distance from it. To say that this is due to the “force” of gravitation is merely verbal, like saying that opium makes people sleep because it has a dormitive virtue. The modern physicist, therefore, merely states formulæ which determine accelerations, and avoids the word “force” altogether. “Force” was the faint ghost of the vitalist view as to the causes of motions, and gradually the ghost has been exorcized.
Until the coming of quantum mechanics, nothing happened to modify in any degree what is the essential purport of the first two laws of motion, namely this: that the laws of dynamics are to be stated in terms of accelerations. In this respect, Copernicus and Kepler are still to be classed with the ancients; they sought laws stating the shapes of the orbits of the heavenly bodies. Newton made it clear that laws stated in this form could never be more than approximate. The planets do not move in exact ellipses, because of the perturbations caused by the attractions of other planets. Nor is the orbit of a planet ever exactly repeated, for the same reason. But the law of gravitation, which deals with accelerations, was very simple, and was thought to be quite exact until two hundred years after Newton’s time. When it was emended by Einstein, it still remained a law dealing with accelerations.
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It is true that the conservation of energy is a law dealing with velocities, not accelerations. But in calculations which use this law it is still accelerations that have to be employed.
As for the changes introduced by quantum mechanics, they are very profound, but still, to some degree, a matter of controversy and uncertainty.
There is one change from the Newtonian philosophy which must be mentioned now, and that is the abandonment of absolute space and time. The reader will remember a mention of this question in connection with Democritus. Newton believed in a space composed of points, and a time composed of instants, which had an existence independent of the bodies and events that occupied them. As regards space, he had an empirical argument to support his view, namely that physical phenomena enable us to distinguish absolute rotation. If the water in a bucket is rotated, it climbs up the sides and is depressed in the centre; but if the bucket is rotated while the water is not, there is no such effect. Since his day, the experiment of Foucault’s pendulum has been devised, giving what has been considered a demonstration of the earth’s rotation. Even on the most modern views, the question of absolute rotation presents difficulties. If all motion is relative, the difference between the hypothesis that the earth rotates and the hypothesis that the heavens revolve is purely verbal; it is no more than the difference between “John is the father of James” and “James is the son of John.” But if the heavens revolve, the stars move faster than light, which is considered impossible. It cannot be said that the modern answers to this difficulty are completely satisfying, but they are sufficiently satisfying to cause almost all physicists to accept the view that motion and space are purely relative. This, combined with the amalgamation of space and time into space-time, has considerably altered our view of the universe from that which resulted from the work of Galileo and Newton. But of this, as of quantum theory, I will say no more at this time.
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CHAPTER VII Francis Bacon
FRANCIS BACON ( 1561-1626), although his philosophy is in many ways unsatisfactory, has permanent importance as the founder of modern inductive method and the pioneer in the attempt at logical systematization of scientic procedure.
He was a son of Sir Nicholas Bacon, Lord Keeper of the Great Seal, and his aunt was the wife of Sir William Cecil, afterwards Lord Burghley; he thus grew up in the atmosphere of state affairs. He entered Parliament at the age of twenty-three, and became adviser to Essex. None the less, when Essex fell from favour he helped in his prosecution. For this he has been severely blamed: Lytton Strachey, for example, in his Elizabeth and Essex, represents Bacon as a monster of treachery and ingratitude. This is quite unjust. He worked with Essex while Essex was loyal, but abandoned him when continued loyalty to him would have been treasonable; in this there was nothing that even the most rigid moralist of the age could condemn.
In spite of his abandonment of Essex, he was never completely in favour during the lifetime of Queen Elizabeth. With James’s accession, however, his prospects improved. In 1617 he acquired his father’s office of Keeper of the Great Seal, and in 1618 he became Lord Chancellor. But after he had held this great position for only two years, he was prosecuted for accepting bribes from litigants. He admitted the truth of accusation, pleading only that presents never influenced his decision. As to that, any one may form his own opinion, since there can be no evidence as to the decisions that Bacon would have come to in other circumstances. He was condemned to a fine of £40,000, to imprisonment in the Tower during the king’s pleasure, to perpetual banishment from court and inability to hold office. This sentence was only very partially executed. He was not forced to pay the fine, and he was kept in the Tower for only four days. But he was
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compelled to abandon public life, and to spend the remainder of his days in writing important books.
The ethics of the legal profession, in those days, were somewhat lax. Almost every judge accepted presents, usually from both sides. Nowadays we think it atrocious for a judge to take bribes, but even more atrocious, after taking them, to decide against the givers of them. In those days, presents were a matter of course, and a judge showed his “virtue” by not being influenced by them. Bacon was condemned as an incident in a party squabble, not because he was exceptionally guilty. He was not a man of outstanding moral eminence, like his forerunner Sir Thomas More, but he was also not exceptionally wicked. Morally, he was an average man, no better and no worse than the bulk of his contemporaries.
After five years spent in retirement, he died of a chill caught while experimenting on refrigeration by stuffing a chicken full of snow.
Bacon’s most important book, The Advancement of Learning, is in many ways remarkably modern. He is commonly regarded as the originator of the saying “Knowledge is power,” and though he may have had predecessors who said the same thing, he said it with new emphasis. The whole basis of his philosophy was practical: to give mankind mastery over the forces of nature by means of scientific discoveries and inventions. He held that philosophy should be kept separate from theology, not intimately blended with it as in scholasticism. He accepted orthodox religion; he was not the man to quarrel with the government on such a matter. But while he thought that reason could show the existence of God, he regarded everything else in theology as known only by revelation. Indeed he held that the triumph of faith is greatest when to the unaided reason a dogma appears most absurd. Philosophy, however, should depend only upon reason. He was thus an advocate of the doctrine of “double truth,” that of reason and that of revelation. This doctrine had been preached by certain Averroists in the thirteenth century, but had been condemned by the Church. The “triumph of faith”
