Trace the products we buy and use every day from plastics and fabrics to cosmetics and fuels back to their origins, and you'll find that the vast majority were made using stuff that came from deep underground. The factories that make the products of modern life do so, by and large, out of chemicals of various kinds. And those chemicals come from plants powered primarily by fossil fuels that transform feedstocks”also mainly petrochemicals into myriad other compounds. It would be much better for the climate, and possibly better for the global economy as well, to make many of the chemical inputs to industry from living organisms instead of from oil, gas, and coal. We already use agricultural products in this way, of course” we wear cotton clothes and live in wooden houses” but plants are not the only source of ingredients. Microbes arguably offer even more potential, in the long term, to make inexpensive materials in the incredible variety of properties that we now take for granted. Rather than digging the raw materials of modern life from the ground, we can instead brew them in giant bioreactors filled with living microorganisms.