"It seems to me that many theories of the universe may be dismissed at once, not as too good, but as too cosy, to be true. One feels sure that they could have arisen only among people living a peculiarly sheltered life at a peculiarly favourable period of the world's history. No theory need be seriously considered unless it recognises that the world has always been for most [humans] and all animals other than domestic pets a scene of desperate struggle in which great evils are suffered and inflicted."