The relationship is sometimes expressed by saying that the more highly differentiated the organism the fewer the offspring. According to Plate we ought to say that, the greater the capacity for parental care the fewer the offspring. This, however, comes to the same thing, since it is the higher organisms which possess the increased capacity for parental care. Putting it in the most generalized zoological way, diminished offspring is the response to improved environment. Thus in Man the decline of the birth-rate, as Professor Benjamin Moore remarks (British Medical Journal, August 20, 1910, p. 454), is "the simple biological reply to good economic conditions. It is a well-known biological law that even a micro-organism, when placed in unfavourable conditions as to food and environment, passes into a reproductive phase, and by sporulation or some special type produces new individuals very rapidly. The same condition of affairs in the human race was shown even by the fact that one-half of the births come from the least favourably situated one-quarter of the population. Hence, over-rapid birth-rate indicates unfavourable conditions of life, so that (so long as the population was on the increase) a lower birth-rate was a valuable indication of a better social condition of affairs, and a matter on which we should congratulate the country rather than proceed to condolences."