When you step away from doing something that you have always been doing and then you return to it, you have a different perspective. You get that desire and the will to strike at everything.
Reality, in its quantitative aspect, must be considered as a system of populations. . . The general study of the equilibria and dynamics of populations seems to have no name; but as it has probably reached its highest development in the biological study known as 'ecology,' this name may well be given to it.