the Song government was the first to issue paper money as banknotes. the World Population Clock estimates that there are 7.8 billion people in the world today. how many millennia did it take to get to that first billion, how exponential and accelerating is that growth. the stock market! antibiotics! iPhones! pizza delivery at 2am! how many bacteria or fungal spores or virus molecules are in every breath we breathe. whether or not the universe is expanding. if you water any handful of dirt, something grows. one could make the argument that bees are the sexual organs of flowers. the crystalized bones of the “cave of glowing skulls.” “‘Purse’ could mean both scrotum and uterus in Renaissance English.” every king was just a person. every person is just a person. sort of. hummingbirds eat half their body weight in sugar daily. if you haven’t driven across I-40 through Oklahoma I don’t think you know enough to consider yourself educated about American Politics. juvenile salmon, gathering at the mouths of rivers before venturing out to sea, have to practice schooling behaviors, first in twos, then in larger and larger groups, until the whole population can swarm and flash together. Mansa Musa, the richest man to ever live, so far, and his retinue of twelve thousand slaves. I don’t know. I see a picture on the internet of a bustling crowded street with its colorful buses and billboards of Kumasi. my dog is panting next to me in the summer heat on the deck I built with wood probably from pine plantations in the Pacific Northwest and I don’t know where the steel for the screws comes from, or all the parts of the drill, each tiny piece fitting into a working electronic mechanism. the ornate temples of Madurai. the paintings of black men with wings. what each culture does to honor their dead. who made the clothes that you wear. how many early human cultures died out because they lost fire. it just went out. there is a theory that the sensation of falling that wakes you up in a sheer panic right before you fall asleep is vestigial from when we slept in trees, but there’s no way to know, about something like that. no other species on earth has built spaceships. many species of birds form migratory flocks together, millions of birds all flying great distances together in huge herds, landing on streambanks and fields and pastures along the way. the cacophony of the grackles roosting in trees in parking lots in Texas. if the power grid went down I wouldn’t know how to make electricity. electric eels can produce shocks of 500 volts. the disputed stories of the giant catfish below the Hoover Dam. rumors of mass graves under Tulsa. “The expansion of the universe is the increase in distance between any two given gravitationally unbound parts of the observable universe with time. It is an intrinsic expansion whereby the scale of space itself changes. The universe does not expand ‘into’ anything and does not require space to exist ‘outside’ it.”