I have long said as much, how humans spend much of their energy, not hunting, groom8ng, napping, mating or socializing, but chasing after pieces of green paper. Their housing, mates, food, their safety, everything depends on these pieces of green paper, which they cannot eat or sleep upon and which have no real use that I can see. These days, the "green paper" itself may not physically even exist, just be in the form of electrons, ciphers in a bank they never have visited. Yet humans every day kill and die for these.

This system is so unnatural that their offspring have to be instructed in it for years, while a six week old kitten knows that mice are for chasing, sunny spots are for naps, and dogs are best avoided.