PRESIDENTIAL ADDRESS. 597 
vital importance to the individuals composing it, this acuity in recognising 
sounds of different pitch, tone, and timbre, and in detecting their precise 
emotional significance, would grow pari passu with the acquisition of speech. 
From the time the early Primate ancestor of Man took to an arboreal mode 
of life, the sense of hearing has always been keen and especially well-represented, 
though not to the degree that vision is, in the neopallium; but this normal 
acuity of the Primate hearing became enormously heightened, or rather, attuned 
to perceive a much greater variety of sounds, when it came to be the chief means 
of communication between Men. 
It must be quite evident that the first essential condition of speech must be 
the evolution of an area (usually in the left brain) in which there can be added 
to the vast collection of visual, auditory, tactile, and other complex states of 
consciousness already stored in it, not only the memories of the visual impres- 
sions of gestures and their meanings, but also of sounds and their associated 
ideas—that is, the state of consciousness which each particular sound awakens, 
through being linked up in memory with the auditory sensation ; and the second 
essential must be a motor cortex sufficiently skilled to produce similar gestures, 
grimaces, and sounds. But just as a child must learn the meaning of words 
long before he attempts to reproduce the sounds himself, so in the dawn of human 
existence the Ape-Man educated his acoustic cortex to associate definite meanings 
with the sounds that occurred in Nature around him, and no doubt learned to 
imitate them before he began to invent new sounds to express new meanings, 
or.to imitate those emitted by his fellow-Men. If it was the precocious high 
development of the sense of sight that started the Primates on their career, the 
high development of the cortical mechanism for discriminating sounds played 
a great part in making Man from an Ape. I think that most anthropologists who 
approach the study of speech from the physical or biological side have concen- 
trated too much attention upon the supposed motor centres, and not enough on 
the great temporo-parietal areas, upon the education of which the faculty of 
speech, as Pierre Marie is rightly insisting, so largely depends. In other words, 
our Simian ancestor must have had something to say before he attempted to find 
means of expressing it. 
I do not propose to discuss the tremendous impetus that the invention of 
speech must have given to human progress and intellectual development, in 
enabling the knowledge acquired by each individual to become the property of 
the community and be handed on to future generations, as well as by supplying 
in words the very symbols and the indispensable elements of the higher mental 
processes. This theme has been frequently discussed by many great thinkers : 
it has been expounded by several of my predecessors in this chair, and its influence 
pictured much more graphically and eloquently than I am capable of doing. For 
as Huxley has well said: Man ‘alone possesses the marvellous endowment of 
intelligible and rational speech, whereby, in the secular period of his existence, 
he has slowly accumulated and organised the experience which is almost wholly 
lost with the cessation of life in other animals; so that now he stands raised upon 
it as on a mountain top, far above the level of his humble fellows, and trans- 
figured from his grosser nature by reflecting here and there a ray from the infinite 
source of truth.’ 44 
We are apt to forget the immensity of the heritage that has come down to us 
from former generations of Men, until we begin dimly to realise that for the 
vast majority of mankind almost the sum-total of their mental activities consists 
of imitation or acquiring and using the common stock of knowledge. For this 
accumulation of knowledge and its transmission to our generation we are almost 
wholly indebted to the use of speech. In our forgetfulness of these facts we 
marvel at the apparent dulness of early Man in being content to use the most 
roughly chipped flints for many thousands of years before he learned to polish 
them, and eventually to employ materials better suited for the manufacture of 
implements and weapons, But is the more highly cultured and civilised popula- 
tion of our own day so much more fertile of ideas? Is it not the fact that no 
really new idea ever enters the mind of the vast majority of mankind, and even 
much that seems new is really compounded of the knowledge gained by others? 
When we consider how slowly and laboriously primitive Man acquired new ideas, 
“* Quoted by Sollas, op. cit., p. Ixxxvii. 
