SIR ISAAC NEWTON

[Isaac Newton was born at Woolsthorpe, in Lincolnshire, on 25th December 1642. He was educated at Grantham and at Trinity College, Cambridge, where he took his degree in 1665. He had already begun to make discoveries in mathematics, and it was in 1666 that the fall of the famous apple suggested to him a rudimentary theory of gravitation. This was not however finally worked out until the Philosophie Naturalis Principia Mathematica of 1687, and in the meantime he occupied himself largely with the phenomena of Light and Optics. He became a Fellow of Trinity in 1667, Lucasian Professor of Mathematics in 1669, a Fellow of the Royal Society in 1691, and its President in 1703. He always held his public duties higher than his scientific, championed his University against James II., sat in Parliament in 1689, and again for the University in 1701, and served as Master of the Mint from 1699. In 1703 he was knighted; died in 1727, and was buried in Westminster Abbey. The best edition of the Principia is that by Sir W. Thomson and Professor Blackburn (1871). His Optics were published in a Latin translation in 1706, his Optical Lectures in 1728, and his Treatise on Fluxions in 1736. He also wrote several pamphlets on theological subjects. His collected Works were edited by Horsley in 1779-1785. The student may consult Sir David Brewster's Life of Newton (1855), and Prof. Augustus de Morgan's Newton, his Friend, and his Niece (1885).]

IN the history of science, especially in its mathematical branches, the activity of Isaac Newton is one of the greatest epochs. A profundity of physical research, combined with a positive genius for the invention of new and fertile mathematical methods, enabled him to accomplish once for all the determination of that vast system of cosmic laws at which generations of explorers Copernicus, Galileo, Kepler- had been vaguely labouring. Subsequent investigation in the same field has been but the elaboration of principles which he laid down. With Aristotle and Darwin he stands in the front rank of the torchbearers of luminous theory.

Newton has indeed but little direct claim to rank among

the masters of English prose. With the exception of a few letters and theological pamphlets, his writings are all in Latin, academic instincts teaching him the inestimable value of that language as an instrument of definite and precise statement. Nor are the subjects such as to leave much room for beauty of form in their exposition. Order, lucidity, and a reverence for the syllogism-you can expect no more from a mathematician. And those same virtues of clear and cogent reasoning, are the chief qualities which Newton carries with him when he ventures into his mother tongue, and beyond the sphere of physics. Indirectly, however, he must have had a considerable influence upon the subsequent course of literature. The impulse of the scientific spirit is among the principal factors to be taken account of in examining the problem of the eighteenthcentury mind; and no one had a greater share in the propagation of this impulse than Newton. Science came, as it were, to be a tonic to the exhausted energies of English literature: it strengthened the nerve, purged the brain of fantastic cobwebs, forced the eye to look at things in the broad commonplace light of day, refreshed and revitalised the whole organism, as the giant of old was refreshed and revitalised, by a healthy touch of earth. There followed a period of infertility, it is true; the manuring season is rarely rich in crops; but the harvest came in time, more swelling and more golden for the long delay. And but for the eighteenth century, with its want of poetic imagination, with its dominant scientific spirit, this rejuvenescence, this regeneration would have been impossible.

E. K. CHAMBERS.

ON THE BELIEF IN A GOD

SIR, When I wrote my treatise about our system, I had an eye upon such principles as might work with considering men, for the belief of a Deity, and nothing can rejoice me more than to find it useful for that purpose. But if I have done the public any service this way, it is due to nothing but industry and patient thought.

As to your first query, it seems to me that if the matter of our sun and planets, and all the matter of the universe, were evenly scattered throughout all the heavens, and every particle had an innate gravity towards all the rest, and the whole space, throughout which this matter was scattered, was but finite; the matter on the outside of this space would by its gravity tend towards all the matter on the inside, and by consequence fall down into the middle of the whole space, and there compose one great spherical mass. But if the matter was evenly disposed throughout an infinite space, it could never convene into one mass, but some of it would convene into one mass, and some into another, so as to make an infinite number of great masses, scattered at great distances from one another throughout all that infinite space. And thus might the sun and fixed stars be formed, supposing the matter were of a lucid nature. But how the matter should divide itself into two sorts, and that part of it, which is fit to compose a shining body, should fall down into one mass and make a sun, and the rest, which is fit to compose an opaque body, should coalesce, not into one great body, like the shining matter, but into many little ones; or if the sun at first were an opaque body like the planets, or the planets lucid bodies like the sun, how he alone should be changed into a shining body, whilst all they continue opaque, or all they be changed into opaque ones, whilst he remains unchanged, I do not think explicable by mere natural causes,

but am forced to ascribe it to the counsel and contrivance of a voluntary Agent.

The same power, whether natural or supernatural, which placed the sun in the centre of the six primary planets, placed Saturn in the centre of the orbs of his five secondary planets, and Jupiter in the centre of his four secondary planets, and the earth in the centre of the moon's orb; and therefore had this cause been a blind one, without contrivance or design, the sun would have been a body of the same kind with Saturn, Jupiter, and the earth, that is, without light and heat. Why there is

one body in our system qualified to give light and heat to all the rest, I know no reason, but because the Author of the system thought it convenient; and why there is but one body of this kind I know no reason, but because one was sufficient to warm and enlighten all the rest. For the Cartesian hypothesis of suns losing their light, and then turning into comets, and comets into planets, can have no place in my system, and is plainly erroneous; because it is certain that as often as they appear to us, they descend into the system of our planets, lower than the orb of Jupiter, and sometimes lower than the orbs of Venus and Mercury, and yet never stay here, but always return from the sun with the same degrees of motion by which they approached him.

To your second query, I answer, that the motions which the planets now have could not spring from any natural cause alone, but were impressed by an intelligent Agent. For since comets descend into the region of our planets, and here move all manner of ways, going sometimes the same way with the planets, sometimes the contrary way, and sometimes in cross ways, in planes inclined to the plane of the ecliptic, and at all kinds of angles, it is plain that there is no natural cause which could determine all the planets, both primary and secondary, to move the same way and in the same plane, without any considerable variation: this must have been the effect of counsel. Nor is there any natural cause which could give the planets those just degrees of velocity, in proportion to their distances from the sun, and other central bodies, which were requisite to make them move in such concentric orbs about those bodies. Had the planets been swift as comets, in proportion to their distances from the sun (as they would have been, had their motion been caused by their gravity, whereby the matter, at