LIFE AND HABIT 105 



its proper " function " or " duty " constitutes the very essence 

 of disease. Darwin at least suspected food as making a difference, 

 whilst Butler, failing in this instance to apply his inspiration as 

 regards the " thoughtfulness of food," is inclined to think that 

 the blame rests " with the inability on the part of the creature 

 reproduced to recognise the new surroundings and, hence, with 

 its failing to know itself," which may be quite true, so far as the 

 mental unfitness goes, but fails to adduce the reason for it. 

 Both Darwin and Butler, I believe, expected too much from a 

 mere cross, as though " crosses " did not depend above all for their 

 results on " moral signs " attached to them, i.e., on the degree 

 of their bio-economic sanction. The mysterious " factor," 

 accounting for the reproductive weakness, for which many have 

 searched, whether connected with food or with memory, or with 

 one of these more than with another, is pre-eminently a bio-econ- 

 omic factor. 



More signally still Butler's explanation breaks down in the 

 case of hybrids " which are born well-developed and healthy, 

 but nevertheless perfectly sterile." 



Here, he thinks, it is less obvious why, having succeeded in 

 understanding the conflicting memories of their parents, they 

 should fail to produce offspring, and he is thus actually driven 

 to attempt what might well be called a qualitative explanation. 



' There must be," he says, " on either side a very long series 

 of sufficiently steady memory." 



The hybrid, continues Butler, may find " one single experi- 

 ence too small to give it the necessary faith, on the strength 

 of which even to try to reproduce itself." In other words, there 

 is a lack of orientation due to an " incompleteness " somewhere 

 probably in the relation with the environment. The case 

 thus recalls the need in health and growth generally of a 

 " complete diet," which need, as we have seen, has a special 

 bio-economic significance. The idea of " mind- vit amines," 

 possibly associated with " food-vitamines " here suggests itself. 

 It would harmonise with Butler's contention that the organism, 

 in order duly to know itself, must be instinct with a deep know- 

 ledge of surroundings. 



Butler further thinks it probable " that all our mental powers 

 must go through a quasi-embryological condition," which, if 

 true, would make it appear all the more likely that Vitamines 

 are required for mind as well as body. To say this is to assert, 



