Science Friction_ Where the Known Meets the Unknown - Michael Shermer [31]
The history of science is filled with such ego-shattering discoveries. Thanks to science, change happens so fast that the world of today is as different as when I was born, during the Eisenhower presidency, as Eisenhower’s world was from George Washington’s. Isn’t there anything in science we can count on to be “true” in some provisional sense? Yes, of course there is. The universe constitutes all that there is. Time travel is impossible. Evolution is progressive and leads to more complex and intelligent life. Oil is a finite fossil fuel of which we are about to run out. You cannot catch cancer. The brain and spinal cord cannot regenerate.
Of these six scientific facts we can be certain, no? No. There are no “facts” in science, in the sense of something being proven 100 percent. Of course, we can make provisional conclusions about which we can be exceptionally confident—and of these we might say they are “facts”—but, strictly speaking, we must be open to new claims, and listen to the scientific heretics who challenge our most cherished assumptions, because if there is one thing that is certain in the history of science, it is that nothing is certain in science. So, as an exercise in skepticism—in the original Greek meaning of that word as “thoughtful inquiry”—let’s consider some serious challenges to these deeply rooted scientific assumptions, provocatively presented as heresies:
Heresy 1: The Universe Is Not All There Is
Heresy 2: Time Travel Is Possible
Heresy 3: Evolution Is Not Progressive
Heresy 4: Oil Is Not a Fossil Fuel
Heresy 5: Cancer Is an Infectious Disease
Heresy 6: The Brain and Spinal Cord Can Regenerate
With each heresy we will consider the belief it is challenging, the alternative it offers, and the likelihood that it is correct.
The Fuzzy Factor
Since these heretical ideas differ in content and certainty, I have devised a “fuzzy factor” rating for the likelihood of them being correct. I originally developed this system for my book The Borderlands of Science to assess claims that fall in that fuzzy gray area between clear science and obvious pseudoscience. These borderlands beliefs may be true, but we don’t know yet, so I assigned them probability figures ranging from.1 (least likely to be true) to .9 (most likely to be true). Nothing gets a zero or a 1 because in science we cannot be that certain.
Consider the color of the sky. Traditional binary logic demands that it must be either blue or nonblue, but not both. In a system of fuzzy logic, however, a fuzzy fraction is a more accurate description. At dawn on the sunrise horizon the sky might be .1 blue and .9 nonblue (or, say, .9 orange). At noon overhead the sky might be .9 blue. At dusk on the sunset horizon the sky might be .2 blue and .8 nonblue (or .8 orange). This system gives us a lot more flexibility in evaluating controversial claims, and allows us to be more tolerant of heretics, so to each of these heresies I have ascribed a “fuzzy factor” between .1 and .9, from least likely to most likely to be true. The evaluations are my own and are thus necessarily personal, so you should, in the best sense of the word, be skeptical not only of the original theories and the heretical challenges to them, but of my assessment as well. In science, as in life, it is best to check things out yourself.
Heresy 1. The Universe Is Not All There Is
In the most watched television documentary series of all time, Cosmos, the astronomer Carl Sagan dramatically defined his subject this way: “The cosmos is all that is, or ever was, or ever will be.” That was in 1980. A lot has changed since then, including the possibility that the universe may not be all there is. There may be more . . . a lot more. The single bubble universe in which we reside, that was born in a big bang and will most likely expand forever and die with a whimper, may be only one of many, perhaps an infinite number of bubble universes, all with slightly different configurations and laws