638 NATURAL SCIENCE. oct., 



is simply to ignore the nature of proof. All that I have ventured to maintain is that, 

 under the conditions of my experiments, tlie action of light determined the produc- 

 tion of pigment on the lower side of flounders. It by no means follows that the 

 occurrence of pigment on the lower side of a flat-fish under natural conditions has 

 been due to the direct action of light. 



In conclusion, I will add a few words of e.xplanation which will, perhaps, enable 

 Professor Giard to understand why I felt it necessary to criticise his note so severely. 

 Like himself, I have a strong leaning towards Lamarckian principles, and I 

 considered that the almost universal fact that pigment is more abundant on the 

 dorsal than on the ventral surfaces of animals, and the fact that whereas in fishes 

 generally the ventral surface, which is turned downwards, is pigmsntless in the flat- 

 fi shes, the whole of the lower side has become pigmentless and the whole of the upper 

 uniformly pigmented, indicated strongly that the incidence of light rays on the skin 

 caused the deposition of pigment. I studied the question of ambicolorate specimens 

 and could find no suflicient evidence that in them the lower sides had been more 

 exposed to light than normal specimens, and I felt that sufficient evidence in a case 

 of this kind could never be got by observation of fishes in their natural wild state, 

 I came to the conclusion that questions of this kind could only be decided by 

 experiment. Having succeeded beyond my expectation, I was naturally indignant 

 when a zoologist of reputation, from whom I had reason to expect sympathy and 

 support, should come forward and publicly depreciate my methods and my results, 

 and endeavour to throw the whole subject into the hopeless quagmire of fallacy 

 ■which I was trying so carefully to avoid. J. T. Cunningham. 



Professor Mivart on the Foundations of Science. 



The ultimate basis of all science (and it is an ultimate basis which forms the 

 object of Professor Mivart's discussion) can be nothing less than the general conditions 

 of consciousness upon which the very possibility of experience depends. It is 

 possible to enunciate a large number of propositions, psychological, logical, or other- 

 wise, which may be self-evident and which may be necessary, but which may yet 

 have no claim to be the foundations of science. Furthermore, the validity of many 

 such propositions remains doubtful so long as their connections with principles more 

 fundamental are still to seek. 



Professor Mivart's " Intelleciualism " seems to be in this predicament ; for as a 

 system it begs the whole question of the theory of cognition. Thus, of the four 

 " essential truths " each of the first three lays down as a postulate without proof or 

 definition (and so presumably as ultimate) what is in truth the very problem to be 

 solved. The first talks o{ substantial and continuous existence, and the second of real 

 existence, without any suggestion of a suspicion that these words raise the whole 

 question as to what is the nature of human knowledge ; while the third even more 

 aively asserts that there are truths which are apart from the existence of any or 

 every mind and that this is matter of knov.dedge. 



As an example to prove that we have knowledge which is not conditioned by 

 our faculties. Professor Mivart instances the case of number. But surely it may be 

 questioned whether " facts concerning number," to use Professor Mivart's phrase,, 

 would exist at all if it were not for our faculties of perception. Thanks to our faculties 

 of perception we have objects to count, and if intuition did not give us objects to count,. 

 can we suppose that numbers would have for us any significance whatever ? 



The objection which Professor Mivart makes to the Kantian view of Space and 

 Time (which, indeed, has often been made and refuted before) does not seem to me 

 serious, because it is really irrelevant. Space and Time certainly do take their 

 place as abstractions whenever in the course of our studies we make them the 

 objects of empirical thought. As abstractions, they then come before us among 

 other contents of consciousness. But the fact that we can or must think of them, 

 thus when we treat them as objects has nothing to do with the question as to 

 whether they have a just claim to be regarded as fundamental conditions of the 

 production of experience by sensuous intuition. 



The "other truth " which Professor Mivart puts forward as of special impor- 



