thing like a general idea of water, a pure (generic) image being all that seems necessary. On the other hand, one is disposed, on the evidence of the facts adduced by our author, to put the beginnings of the true generalizing process pretty low down. It certainly seems to be involved in the mental life of the ants, as elicited by Sir John Lubbock's experiments, and described by Dr. Romanes (p. 94 and following). And since these particular actions plainly imply the use of signs, and apparently signs capable of indicating such abstract ideas as those of quantity, there seems no reason why we should hesitate to call ants thinkers in the sense of being able to form general notions. The same applies to the mechanical inventions of the spider, described by Mr. Larkin (p. 62). Similarly, it is difficult to deny the rudiment of "conceptual thought" to a fox who can reason on the matter of traps in the way described by Leroy (p. 56), or to a dog that was cured of his dread of imagined thunder by being shown the true cause of the disturbing noise, viz., the shooting bags of apples on to a floor (pp. 59, 60). No doubt there is a danger in straightway endowing animals with mental qualities identical with our own, when their actions resemble ours. There may, of course, be two psychological explanations of the same action. We can not, however, escape our limitations, and, if we are to deal with animal ways at all, we are bound to interpret them in terms of our own mental processes.
The hesitation of the evolutionist to attribute rudimentary thought to animals, in which Dr. Romanes evidently shares, is no doubt due to the firmly established assumption that we generalize by help of language. To the nominalist more especially it savors of rank heresy to hint that animals apparently destitute of signs may be capable of generalizing their perceptions and reaching a dim consciousness of the distinction between the universal and the particular.
But is the nominalist's assumption that language is the indispensable instrument of thought above challenge? A considerable part of Dr. Romanes's volume deals with the relations of thought to language. He gives us a fairly good summary of the results of research into the origin of language. It can not be said that these throw much light on the question. Perhaps it is unreasonable to expect that they should. Our author contends with some skill as against Prof. Max Müller that the earliest traces of human language suggest a highly pictorial and non-conceptual mode of ideation. And in his ingenious hypothetical account of the genealogy of man as the articulate reasoner our author inclines to the idea that, so far from language making the thinker, the endowment of language has to be ingrafted on a high quality of intelligence, and even then to undergo considerable development before it becomes a mechanism for conceptual thought.
