Pale Blue Dot - Carl Sagan [15]
As for humans, we’re latecomers. We appear in the last instant of cosmic time. The history of the Universe till now was 99.998 percent over before our species arrived on the scene. In that vast sweep of aeons, we could not have assumed any special responsibilities for our planet, or life, or anything else. We were not here.
Well, if we can’t find anything special about our position or our epoch, maybe there’s something special about our motion. Newton and all the other great classical physicists held that the velocity of the Earth in space constituted a “privileged frame of reference.” That’s actually what it was called. Albert Einstein, a keen critic of prejudice and privilege all his life, considered this “absolute” physics a remnant of an increasingly discredited Earth chauvinism. It seemed to him that the laws of Nature must be the same no matter what the velocity or frame of reference of the observer. With this as his starting point, he developed the Special Theory of Relativity. Its consequences are bizarre, counterintuitive, and grossly contradict common sense—but only at very high speeds. Careful and repeated observations show that his justly celebrated theory is an accurate description of how the world is made. Our commonsense intuitions can be mistaken. Our preferences don’t count. We do not live in a privileged reference frame.
One consequence of special relativity is time dilation—the slowing down of time as the observer approaches light speed. You can still find claims that time dilation applies to watches and elementary particles—and, presumably, to circadian and other rhythms in plants, animals, and microbes—but not to human biological clocks. Our species has been granted, it is suggested, special immunity from the laws of Nature, which must accordingly be able to distinguish deserving from undeserving collections of matter. (In fact, the proof Einstein gave for special relativity admits no such distinctions.) The idea of humans as exceptions to relativity seems another incarnation of the notion of special creation:
Well, even if our position, our epoch, our motion, and our world are not unique, maybe we are. We’re different from the other animals. We’re specially created. The particular devotion of the Creator of the Universe is evident in us. This position was passionately defended on religious and other grounds. But in the middle nineteenth century Charles Darwin showed convincingly how one species can evolve into another by entirely natural processes, which come down to the heartless business of Nature saving the heredities that work and rejecting those that don’t. “Man in his arrogance thinks himself a great work worthy [of] the interposition of a deity,” Darwin wrote telegraphically in his notebook. “More humble and I think truer to consider him created from animals.” The profound and intimate connections of humans with the other life forms on Earth have been compellingly demonstrated in the late twentieth century by the new science of molecular biology.
IN EACH AGE the self-congratulatory chauvinisms are challenged in yet another arena of scientific debate—in this century, for example, in attempts to understand the nature of human sexuality, the existence of the unconscious mind, and the fact that many psychiatric illnesses and character “defects” have a molecular origin. But also:
Well, even if we’re closely related to some of the other animals, we’re different—not just in degree, but in