Part 16

SIMPLICIUS: I believe that the Peripatetics----

SALVIATUS: I do not ask the Peripatetics, I ask Aristotle. As for the Peripatetics, they, as humble vassals of Aristotle, would deny all the experiments and all the observations in the world; nay, would also refuse to see them, and would say that the universe is as Aristotle writeth, and not as Nature will have it; for, deprived of the shield of his authority, with what do you think they would appear in the field? Tell me, therefore, what Aristotle himself would do.

SIMPLICIUS: To tell you the truth, I do not know how to decide which is the lesser inconvenience.

SALVIATUS: Seeing you do not know, let us examine which would be the more rational choice, and let us assume that Aristotle would have chosen so. Granting with Aristotle that the universe has a spherical figure and moveth circularly round a centre, it is reasonable to believe that the starry orbs move round the centre of the universe or round some separate centre?

SIMPLICIUS: I would say that it were much more reasonable to believe that they move with the universe round the centre of the universe.

SALVIATUS: But they move round the sun and not round the earth; therefore the sun and not the earth is the centre of the universe.

SIMPLICIUS: Whence, then, do you argue that it is the sun and not the earth that is the centre of the planetary revolutions?

SALVIATUS: I infer that the earth is not the centre of the planetary revolutions because the planets are at different times at very different distances from the earth. For instance, Venus, when it is farthest off, is six times more remote from us than when it is nearest, and Mars rises almost eight times as high at one time as at another.

SIMPLICIUS: And what are the signs that the planets revolve round the sun as centre?

SALVIATUS: We find that the three superior planets--Mars, Jupiter, and Saturn--are always nearest to the earth when they are in opposition to the sun, and always farthest off when they are in conjunction; and so great is this approximation and recession that Mars, when near, appears very nearly sixty times greater than when remote. Venus and Mercury also certainly revolve round the sun, since they never move far from it, and appear now above and now below it.

SAGREDUS: I expect that more wonderful things depend on the annual revolution than upon the diurnal rotation of the earth.

SALVIATUS: YOU do not err therein. The effect of the diurnal rotation of the earth is to make the universe seem to rotate in the opposite direction; but the annual motion complicates the particular motions of all the planets. But to return to my proposition. I affirm that the centre of the celestial convolutions of the five planets--Saturn, Jupiter, Mars, Venus, and Mercury, and likewise of the earth--is the sun.

As for the moon, it goes round the earth, and yet does not cease to go round the sun with the earth. It being true, then, that the five planets do move about the sun as a centre, rest seems with so much more reason to belong to the said sun than to the earth, inasmuch as in a movable sphere it is more reasonable that the centre stand still than any place remote from the centre.

To the earth, therefore, may a yearly revolution be assigned, leaving the sun at rest. And if that be so, it follows that the diurnal motion likewise belongs to the earth; for if the sun stood still and the earth did not rotate, the year would consist of six months of day and six months of night. You may consider, likewise, how, in conformity with this scheme, the precipitate motion of twenty-four hours is taken away from the universe; and how the fixed stars, which are so many suns, are made, like our sun, to enjoy perpetual rest.

SAGREDUS: The scheme is simple and satisfactory; but, tell me, how is it that Pythagoras and Copernicus, who first brought it forward, could make so few converts?

SALVIATUS: If you know what frivolous reasons serve to make the vulgar, contumacious and indisposed to hearken, you would not wonder at the paucity of converts. The number of thick skulls is infinite, and we need neither record their follies nor endeavour to interest them in subtle and sublime ideas. No demonstrations can enlighten stupid brains.

My wonder, Sagredus, is different from yours. You wonder that so few are believers in the Pythagorean hypothesis; I wonder that there are any to embrace it. Nor can I sufficiently admire the super-eminence of those men's wits that have received and held it to be true, and with the sprightliness of their judgments have offered such violence to their senses that they have been able to prefer that which their reason asserted to that which sensible experience manifested. I cannot find any bounds for my admiration how that reason was able, in Aristarchus and Copernicus, to commit such a rape upon their senses, as in despite thereof to make herself mistress of their credulity.

SAGREDUS: Will there still be strong opposition to the Copernican system?

SALVIATUS: Undoubtedly; for there are evident and sensible facts to oppose it, requiring a sense more sublime than the common and vulgar senses to assist reason.

SAGREDUS: Let us, then, join battle with those antagonistic facts.

SALVIATUS: I am ready. In the first place, Mars himself charges hotly against the truth of the Copernican system. According to the Copernican system, that planet should appear sixty times as large when at its nearest as when at its farthest; but this diversity of magnitude is not to be seen. The same difficulty is seen in the case of Venus. Further, if Venus be dark, and shine only with reflected light, like the moon, it should show lunar phases; but these do not appear.

Further, again, the moon prevents the whole order of the Copernican system by revolving round the earth instead of round the sun. And there are other serious and curious difficulties admitted by Copernicus himself. But even the three great difficulties I have named are not real. As a matter of fact, Mars and Venus do vary in magnitude as required by theory, and Venus does change its shape exactly like the moon.

SAGREDUS: But how came this to be concealed from Copernicus and revealed to you?

SIR FRANCIS GALTON

Essays in Eugenics

Sir Francis Galton, born at Birmingham, England, in 1822, was a grandson of Dr. Erasmus Darwin. He graduated from Trinity College, Cambridge, in 1844. Galton travelled in the north of Africa, on the White Nile and in the western portion of South Africa between 1844 and 1850. Like his immortal cousin, Charles Darwin, Sir Francis Galton is a striking instance of a man of great and splendid inheritance, who, also inheriting wealth, devotes it and his powers to the cause of humanity. He published several books on heredity, the first of which was "Hereditary Genius." The next "Inquiries into Human Faculty," which was followed by "Natural Inheritance." The "Essays in Eugenics" include all the most recent work of Sir Francis Galton since his return to the subject of eugenics in 1901. This volume has just been published by the Eugenics Education Society, of which Sir Francis Galton is the honorary president. As epitomised for this work, the "Essays" have been made to include a still later study by the author, which will be included in future editions of the book. The epitome has been prepared by special permission of the Eugenics Education Society, and those responsible hope that it will serve in some measure to neutralise the outrageous, gross, and often wilful misrepresentations of eugenics of which many popular writers are guilty.

I.--The Aims and Methods of Eugenics

The following essays help to show something of the progress of eugenics during the last few years, and to explain my own views upon its aims and methods, which often have been, and still sometimes are, absurdly misrepresented. The practice of eugenics has already obtained a considerable hold on popular estimation, and is steadily acquiring the status of a practical question, and not that of a mere vision in Utopia.