Зображення сторінки
PDF
ePub

2. That it could not have developed that high esteem for acts of care and tenderness to the aged and infirm which actually exists, but would rather have perpetuated certain low social conditions which obtain amongst certain

savage tribes.

3. That it could not have evolved from ape sensations the noble virtue of a Marcus Aurelius, or the loving but manly devotion of a St. Lewis.

4. That, alone, it could not have given rise to the maxim fiat justitia, ruat cælum.

5. That the interval between material and formal morality is one altogether beyond its power to traverse.

Also, that the anticipatory character of moral principles is a fatal bar to that explanation of their origin which is offered to us by Mr. Herbert Spencer. And, finally, that the solution of that origin proposed recently by Sir John Lubbock is a mere version of simple utilitarianism, appealing to the pleasure or safety of the individual, and therefore utterly incapable of solving the riddle it endeavours to explain.

Such appearing to be the case as to the power of “ Natural Selection,” we nevertheless find moral conceptions-formally moral ideas—not only spread over the civilized world, but manifesting themselves unmistakably (in however rudimentary a condition, and however misapplied) amongst the lowest and most degraded of savages. If from amongst these, individuals can be brought forward who seem to be destitute of any moral conception, similar cases also may easily be found in highly civilized communities. Such cases tell no more against moral intuitions than do cases of colour-blindness or idiotism tell against sight and reason. We have then, in distinct moral per

ception, a highly important and conspicuous fact, the existence of which is fatal to the theory of “Natural Selection," as put forward of late by Mr. Darwin and his most ardent followers. It must be remarked, however, that whatever force this fact may have against a belief in the origination of man from brutes by minute, fortuitous variations, it has no force whatever against the conception of the orderly evolution and successive manifestation of specific forms by ordinary natural law-even if we include amongst such the upright frame, the ready hand and massive brain of man himself.

CHAPTER X.

PANGENESIS.

A “ provisional hypothesis” supplementing “Natural Selection."-State

ment of the hypothesis. —Difficulty as to multitude of gemmules—as to certain modes of reproduction—as to formations without the requisite gemmules. —Mr. Lewes and Professor Delpino. - Difficulty as to developmental force of gemmules—as to their spontaneous fission.Pangenesis and Vitalism.—Paradoxical reality.–Pangenesis scarcely superior to anterior hypotheses. --Buffon.—Owen.- Herbert Spencer. —“Gemmules” as mysterious as “physiological units.”—Conclusion.

In addition to the theory of “ Natural Selection," by which it has been attempted to account for the origin of species, Mr. Darwin has also put forward what he modestly terms

a provisional hypothesis” (that of Pangenesis), by which to account for the origin of each and every individual form.

Now, though the hypothesis of Pangenesis is no necessary part of "Natural Selection," still any treatise on specific origination would be incomplete if it did not take into consideration this last speculation of Mr. Darwin's. The hypothesis in question may be stated as follows: That each living organism is ultimately made up of an almost infinite number of minute particles, or organic atoms, termed "gemmules,” each of which has the power of reproducing its kind. Moreover, these particles are sup

posed to circulate freely about the organism (which is made up of them), and to be derived from all the parts of all the organs of the less remote ancestors of each such organism during all the states and stages of such several ancestors' existence; and therefore of the several states of each of such ancestors’ organs. It is further supposed that such a complete collection of gemmules is aggregated in each ovum and spermatozoon in most animals, and in each part capable of reproducing by gemmation (budding) in the lowest animals and in plants.

In many of such lower organisms, therefore, such a congeries of ancestral gemmules must exist in every part of their bodies, since in them every part is capable of reproducing by gemmation. Mr. Darwin must evidently admit this, since he says: “It has often been said by naturalists that each cell of a plant has the actual or potential capacity of reproducing the whole plant; but it has this power only in virtue of containing gemmules derived from every part.1

Moreover, these gemmules are supposed to tend to aggregate themselves, and to reproduce in certain definite relations to other gemmules. Thus, when the foot of an eft is cut off, its reproduction is explained by Mr. Darwin as resulting from the aggregation of those floating gemmules which come next in order to those of the cut surface, and the successive aggregations of the other kinds of gemmules which come after in regular order. Also, the most ordinary processes of repair are similarly accounted for, and the successive development of similar parts and organs in creatures in which such complex evolutions occur is explained in the same way, by the independent action of separate gemmules.

1 “Animals and Plants under Domestication," vol. ii. p. 403.

In order that every living creature may be thus furnished, the number of such gemmules in each must be inconceivably great. Mr. Darwin says :1 “In a highly organized and complex animal the gemmules thrown off from each different cell or unit throughout the body must be inconceivably numerous and minute. Each unit of each part, as it changes during development—and we know that some insects undergo at least twenty metamorphoses --must throw off its gemmules. All organic beings, moreover, include many dormant gemmules derived from their grandparents and more remote progenitors, but not from all their progenitors. These almost infinitely numerous and minute gemmules must be included in each bud, ovule, spermatozoon, and pollen grain.” We have seen also that in certain cases a similar multitude of gemmules must be included in every considerable part of the whole body of each organism ; but where are we to stop ? There must be gemmules not only from every organ, but from every component part of such organ, from every subdivision of such component part, and from every cell, thread or fibre entering into the composition of such subdivision. Moreover, not only from all these, but from each and every single stage of the evolution and development of such successively more and more elementary parts. At the first glance this new atomic theory has charms from its apparent simplicity, but the attempt thus to follow it out into its ultimate limits and extreme consequences seems to indicate that it is at once insufficient and cumbrous.

Mr. Darwin himself is, of course, fully aware that there must be some limit to this aggregation of gemmules. He

1 “ Animals and Plants under Domestication,” vol. ii, p. 366.

« НазадПродовжити »