Here's one reason:

Whether you credit "God", or "Nature", or a "Prime Mover" (before the Big Bang, and/or Evolution), it has taken millions to billions of years (according to both religious belief and science) for the present Creation or Natural Order of Life to evolve. We didn't do it. As human-type beings we are only one factor in a complex, interwoven, mutually-dependent web of life. With Our growing powers, we are fully capable of destroying ourselves as well as other living beings that now form an intricate working Whole. We cannot dismantle or replace this natural, ordered Whole, of which we are one part, with a man-made creation or hasty hodge-podge that has no blueprint, and expect to survive. We are not -- despite the thrill of new knowledge and the chance to make a grab -- super duper supermen. We are super animals without a plan. The tail -- albeit a talented one -- wagging the dog. The crew, happily chopping holes in the boat.

How many times will Cain kill Abel again-- in all his forms-- and congratulate himself again on being the best and only worthy in their Maker's eyes?

'"I have to cast my lot with those who, age after age, Perversely, with no extraordinary power, reconstitute the world. " - Adrienne Rich

Some start by planting trees.

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