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tation, in the number and size of the parts, to the effect to be produced, he breaks out into this remarkable apostrophe: *"How can a man of any intelligence refer all this to chance, as its cause: or, if he deny this to be the effect of foresight and skill, I would ask, what is there that foresight and skill do effect? For surely where chance or fortune act, we see not this correspondence and regularity of parts. I am not very solicitous about terms; but if you choose to call that chance which has so nicely constructed and so justly distributed all the parts of an animal body, do so; only remember and allow, that in so doing you do not fairly exercise the privilege of framing new terms: for in this way you may call the meridian splendour of the sun by the name of night; and the sun itself, darkness. What! was it chance that made the skin give way so as to produce a mouth? or, if this happened by chance, did chance also place teeth and a tongue within that mouth? For, if so, why should there not be teeth and a tongue in the nostrils, or in the ear?" Or, to carry on a similar appeal, “did chance dispose the teeth themselves in their present order; which if it were any other than it is, what would be the consequence? If, for instance, the incisors and canine teeth had occupied the back part of the mouth, and the molar or grinding teeth had occupied the front, what use could we have made of either? Shall we then admire the skill of him who disposes a chorus of thirtytwo men in just order; and can we deny the skill of the Creator, in disposing the same number of teeth in an order so convenient, so necessary even for our existence?"

He then extends the argument to the teeth of other animals, as corresponding with the nature of their food; and also to the form of their feet, as having a relation to the character of their teeth.

"Never," says Cuvier, one of the most experienced

* Lib. xi. cap. 7 and 8.

physiologists of the present age, "never do you see in nature the cloven hoof of the ox joined with the pointed fang of the lion; nor the sharp talons of the eagle accompanying the flattened beak of the swan."

In corresponding expressions Galen exclaims, *"How does it happen that the teeth and talons of the leopard and lion should be similar; as also the teeth and hoofs of the sheep and goat; that in animals which are by nature courageous, there should be found sharp and strong weapons, which are never found in those animals that are by nature timid: or, lastly, that in no animal do we meet with a combination of powerful talons with inoffensive teeth? How should this happen, but that they are all the work of a Creator, who ever kept in mind the use and mutual relation of different organs, and the final purpose of all his works?"

CHAPTER IV.

ON THE BRAIN, CONSIDERED AS THE ORGAN OF THE
INTELLECTUAL FACULTIES.

It can no more be doubted that many of the phenomena of nature, and the important practical and philosophical conclusions deduced from them, would have been hitherto concealed from human knowledge, had man failed to exercise those intellectual faculties with which the Creator has endued him; than that political communities would have failed to exist, and social life to be adorned with the arts of civilization, had all mankind determined to pursue the mode of life adopted by savage tribes: nor can it be doubted that the Creator, in imparting to man

*Lib. xi. cap. 8. ed. Kühn. vol. iii. p. 875. lin. 3—17. and p. 892. lin. 12-17.

intellectual faculties superior to those of brutes, intended that he should exercise them, not solely with a view to the higher and future destination of his nature, but also with a view to the purposes of this present life.

Since however the senses of hearing, sight, and touch, which are the great inlets of knowledge, are possessed by many of the inferior classes of animals in common with ourselves, by some indeed in a more exquisite degree; since also those animals are capable of remembering past, and conjecturing future events, although incapable of the more abstract functions of the understanding; it becomes highly interesting to inquire whether there is any thing in the physical structure of man which renders him more capable of being acted on by external agents, with respect to the developement of his intellectual faculties, than brutes are: in other words, whether there is a material instrument in animal organization, the general composition of which is in obvious correspondence with the degree of intellect evinced by different species of animals, including man as one of those species.

Now if any one in the least degree conversant with the laws of optics and of sound, were to doubt the adaptation of the structure of the eye and of the ear to those laws respectively, he would fairly be ranked among the individuals of that class of speculatists whose minds are too weak to apprehend any truth. And though there is not so obvious a relation between the structure of the brain and the exercise of the mental faculties, as in the case of the eye and light, and of the ear and sound; yet the indications of a natural connexion between the two are both clear and numerous. And hence not only have philosophical inquirers in all ages acknowledged such a connexion; but the most common observers have ever felt an intuitive conviction of its existence, and have considered the brain as the instrument of

thought and reason: the truth of which assertion is evident from various metaphorical terms expressive both of intellectual defect and of intellectual excellence.

It may be presumed that, without the aid afforded by the study of anatomy or natural history, the most cursory observer might discover that the indications of intelligence manifested by the various classes of animals generally correspond in degree with their approximation in physical structure to man; and that, if we confine our view to the four highest classes, namely, fish, reptiles, birds, and quadrupeds, and consider them with reference to their respective degree of docility; fish and reptiles, which are the lowest in the scale, will readily be allowed to be inferior to birds, which are a degree higher in the scale; and these again will with equal readiness be allowed to be inferior to quadrupeds, which are the highest.

And it would be acknowledged upon a more accurate investigation, that, although there are at first sight some seeming exceptions to the regularity of gradation, the apparent anomalies vanish when put to the test of a philosophical examination. Should it be said, for instance, that the bee or the ant shows greater indications of intelligence than many species much higher in the scale of animal creation, it may be answered that those indications are manifested in actions which are referable to instinct, rather than intelligence; actions namely, which being essential to the existence of the individuals, and the preservation of the species, are apparently determined by some internal impulse which animals unconsciously obey. Nor does it militate against such a notion of instinct, that when accidental impediments prevent

* 66

-and his pure brain,

Which some suppose the soul's frail dwelling house,
Doth, by the idle comments which it makes,

Foretell the ending of mortality."

King John, Act 5, Scene 7.

the regular evolution of the comb, taking that as an instance, the bee accommodates the arrangement of its fabric to the impediment which is placed in its way: for such a modification of instinct is as clearly necessary in the case of an occasional impediment, as instinct itself is necessary for the general purpose. In speaking of instinct I purposely avoid a formal definition of the term: for any attempt to define with accuracy a principle, of the real nature of which we are ignorant, usually leaves us in a state of greater darkness than we were before; of which the following extraordinary attempt, with reference to the very principle now under consideration, is a sufficient illustration. It is quoted from an author of the name of Wagner, in a work on the Brain of Man and other Animals, written by Wenzel and his brother; and is as follows: "The instincts of animals are nothing more than inert or passive attractions derived from the power of sensation: and the instinctive operations of animals nothing more than crystallizations produced through the agency of that power.'

Of the general position, then, that the brain is the instrument of intelligence, and that the degree of intelligence characteristic of different classes of animals is proportional to the approximation of their structure to that of man, it may for the present be presumed that no one doubts,

*Instinctus animalium nihil aliud sunt, quam attractiones mortuæ a sensibilitate profecta; et eorum artificia nihil aliud quam crystallizationes per sensibilitatem productæ. Wenzel, De penitiori Structura Cerebri. Tubingæ, fol. 1812. p. 248, lib. x.

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