Darwin on the Development of the Human Mind

By Unknown - Karl Pearson (1914-30) The life, letters and labours of Francis Galton, IIIa, Cambridge: University press, p. 341 OCLC: 873074079., Public Domain, https://commons.wikimedia.org/w/index.php?curid=36632165

This is a wonderful summary by Charles Darwin at the end of Chapter IV of the Descent of Man, after he has compared the 'Mental Powers of Man and the Lower Animals':

There can be no doubt that the difference between the mind of the lowest man and that of the highest animal is immense. An anthropomorphous ape, if he could take a dispassionate view of his own case, would admit that though he could form an artful plan to plunder a garden--though he could use stones for fighting or for breaking open nuts, yet that the thought of fashioning a stone into a tool was quite beyond his scope. Still less, as he would admit, could he follow out a train of metaphysical reasoning, or solve a mathematical problem, or reflect on God, or admire a grand natural scene. Some apes, however, would probably declare that they could and did admire the beauty of the coloured skin and fur of their partners in marriage. They would admit, that though they could make other apes understand by cries some of their perceptions and simpler wants, the notion of expressing definite ideas by definite sounds had never crossed their minds. They might insist that they were ready to aid their fellow-apes of the same troop in many ways, to risk their lives for them, and to take charge of their orphans; but they would be forced to acknowledge that disinterested love for all living creatures, the most noble attribute of man, was quite beyond their comprehension.

Nevertheless the difference in mind between man and the higher animals, great as it is, certainly is one of degree and not of kind. We have seen that the senses and intuitions, the various emotions and faculties, such as love, memory, attention, curiosity, imitation, reason, etc., of which man boasts, may be found in an incipient, or even sometimes in a well-developed condition, in the lower animals. They are also capable of some inherited improvement, as we see in the domestic dog compared with the wolf or jackal. If it could be proved that certain high mental powers, such as the formation of general concepts, self-consciousness, etc., were absolutely peculiar to man, which seems extremely doubtful, it is not improbable that these qualities are merely the incidental results of other highly-advanced intellectual faculties; and these again mainly the result of the continued use of a perfect language. At what age does the new-born infant possess the power of abstraction, or become self-conscious, and reflect on its own existence? We cannot answer; nor can we answer in regard to the ascending organic scale. The half-art, half-instinct of language still bears the stamp of its gradual evolution. The ennobling belief in God is not universal with man; and the belief in spiritual agencies naturally follows from other mental powers. The moral sense perhaps affords the best and highest distinction between man and the lower animals; but I need say nothing on this head, as I have so lately endeavoured to shew that the social instincts,--the prime principle of man's moral constitution (50. 'The Thoughts of Marcus Aurelius,' etc., p. 139.)--with the aid of active intellectual powers and the effects of habit, naturally lead to the golden rule, "As ye would that men should do to you, do ye to them likewise;" and this lies at the foundation of morality.

In the next chapter I shall make some few remarks on the probable steps and means by which the several mental and moral faculties of man have been gradually evolved. That such evolution is at least possible, ought not to be denied, for we daily see these faculties developing in every infant; and we may trace a perfect gradation from the mind of an utter idiot, lower than that of an animal low in the scale, to the mind of a Newton. (emphasis mine)

This last point, comparing the ontogeny of humans with our phylogeny, is well made. And this is not to say that ontogeny recapitulates phylogeny, as the famous, but defunct, theory suggests. But it is a counter to those who suggest that a thing as wonderful and mysterious as the human mind could not evolve gradually in mini-steps, by degree, since we have seen, and continue to see, countless examples of the human mind developing gradually in mini-steps, by degree, before our very eyes. Some might insist that a greater power steps in and animates this mind at some point, but this doesn't appear to be what is happening and, when I introspect, it doesn't appear to me to be what happened as I became conscious of my surroundings.

In the end the more parsimonious explanation is that the mental emerges from the physical, not the other way round.