Page:Popular Science Monthly Volume 18.djvu/709

Rh theories. Mental notions can aid us only as they are reflections of nature. Even scientific hypotheses have but a relative validity. In time, as in space, the extent of knowledge follows a law analogous to the law of spherical diffusion. It has been held that the record of any historic event is wholly invalidated by the lapse of sufficient time; much more is this true of future prediction. The baseline of our knowledge is sufficient but for a limited survey. The very distant future has no mental parallax.

We have seen every far-reaching theory become obsolete; and there is no reason to suppose that, at the present time, we shall be more successful. There is but one course that it is safe to pursue, namely, to be content to let insoluble problems remain as such—not attempting any mental theory concerning them—and confine ourselves to those problems that may offer some probability of solution, with the assurance that, however far the boundaries of knowledge may be extended, each successful solution will enlarge the horizon of the unknown beyond.

 

HIS illustrious American mathematician and astronomer died in Boston, October 6, 1880, in the seventy-second year of his age. He was born in Salem, Massachusetts, April 4, 1809. He was graduated at Harvard College at the age of twenty. His father was a graduate of the same institution, and died its librarian. He was appointed tutor in 1831, University Professor of Mathematics and Natural Philosophy in 1833, and Perkins Professor of Astronomy and Mathematics in 1842, and was directly connected with the faculty of the college for forty-nine years. He was a member of all the learned societies in this country and in Europe, was elected Fellow of the Royal Society of England in 1857, and in 1867 received the degree of LL.D. from Harvard University.

We take the liberty of quoting from that excellent periodical, "The Harvard Register," for May, 1880 (to the courtesy of whose editor we are also indebted for the excellent likeness herewith presented), the following account of Professor Peirce's character and work, written, it will be observed, before his death, by Dr. Thomas Hill, ex-President of Harvard University:

"From 1836 to 1846 he issued a series of text-books on geometry, trigonometry, algebra, and 'curves, functions, and forces.' They were so full of novelties that they never became widely popular, except, perhaps, the trigonometry; but they have had a permanent influence upon mathematical teaching in this country; most of their novelties have now become commonplaces in all text-books. The introduction 