Instinct and Educability 443 
and that this method of study offered a wide and rich field for 
investigation. Of course those who regarded the study of mind only 
as a branch of metaphysics smiled at the philosophical ineptitude of 
the mere man of science. But the investigation, on natural history 
lines, has been prosecuted with a large measure of success. Much 
indeed still remains to be done ; for special training is required, and 
the workers are still few. Promise for the future is however afforded 
by the fact that investigation is prosecuted on experimental lines 
and that something like organised methods of research are taking 
form. There is now but little reliance on casual observations recorded 
by those who have not undergone the necessary discipline in these 
methods. There is also some change of emphasis in formulating 
conclusions. Now that the general evolutionary thesis is fully and 
freely accepted by those who carry on such researches, more stress is 
laid on the differentiation of the stages of evolutionary advance than 
on the fact of their underlying community of nature. The conceptual 
intelligence which is especially characteristic of the higher mental 
procedure of man is more firmly distinguished from the perceptual 
intelligence which he shares with the lower animals—distinguished 
now as a higher product of evolution, no longer as differing in origin 
or different in kind. Some progress has been made, on the one hand 
in rendering an account of intelligent profiting by experience under 
the guidance of pleasure and pain in the perceptual field, on lines 
predetermined by instinctive differentiation for biological ends, and 
on the other hand in elucidating the method of conceptual thought 
employed, for example, by the investigator himself in interpreting 
the perceptual experience of the lower animals. 
Thus there is a growing tendency to realise more fully that there 
are two orders of educability—first an educability of the perceptual 
intelligence based on the biological foundation of instinct, and 
secondly an educability of the conceptual intelligence which re- 
fashions and rearranges the data afforded by previous inheritance 
and acquisition. It is in relation to this second and higher order of 
educability that the cerebrum of man shows so large an increase of 
mass and a yet larger increase of effective surface through its rich 
convolutions. It is through educability of this order that the human 
child is brought intellectually and affectively into touch with the 
ideal constructions by means of which man has endeavoured, with 
more or less success, to reach an interpretation of nature, and to 
guide the course of the further evolution of his race—ideal con- 
structions which form part of man’s environment. 
It formed no part of Darwin’s purpose to consider, save in broad 
outline, the methods, or to discuss in any fulness of detail the results 
of the process by which a differentiation of the mental faculties of 
