Chapter 16.                 Part B 

         But as David Hume famously proved, the logic that the scientific method is built on is not perfect. Any natural law that we try to state as a way of describing our observations of reality is a gamble, one that may seem to summarize, and bring order to, whole files of experiences, but a gamble nonetheless. A natural law is a (gambling) scientist's claim about what he thinks is going to happen in specific future circumstances. But every natural law that we may propose is taking for granted a deep first assumption about the real world. That assumption is that events in the future will keep steadily following the patterns that we have been able to spot in the flows of events in the past. Our problem is that we haven't been to the future. We simply can't ever know whether this assumption is true. At any time, we may come on new data that stymie our best theories.

                                          

                                                 

            In short, Science is still open to making mistakes. For scientists themselves, a shocking example of such a mistake was the "mistake" in Newtonian physics. Newton's models of how gravity and acceleration worked were excellent, but they weren't telling the whole story of what goes on in the world. After two centuries of taking Newton's models and equations as gospel, physicists were stunned by the experiment done by Albert Michelson and Edward Morley in 1887. It essentially showed that Newton's laws were not adequate to explain all of what was really going on. Einstein's thinking on these new data is what led him to the Theory of Relativity. But first came Michelson and Morley's experiment, which showed that the scientific method, and Newton, were not infallible.

            Newton was not proved totally wrong, of course, but his laws were shown to be mere rough approximations, accurate only for smaller masses and at slower speeds. As the masses and speeds that we are looking at get larger, Newton's laws become less and less useful for predicting what is going to happen next.    

               

            Nevertheless, we should note, it was a scientist (Einstein) doing science who found the limitations of the laws and models specified by an earlier scientist. Newton was not amended by a clergyman or a reading from an ancient holy text. Thus, from the personal standpoint, I have always believed, I still believe, and I am confident that I always will believe, that the universe is consistent, that it runs by laws which - even though we don't understand all of them very well yet - will be the same in 2525 as they are now. Relativity theory described how the stars moved in the year 100,000,000 B.C. exactly as accurately as it describes the stars’ movements now, and, in that era, living things reproduced and changed by the process that we call "evolution" just as reliably as living things do now. I believe that, for living things, genetic variation and natural selection are constants.

But I can’t prove beyond any doubt that the universe runs by one consistent set of laws; I can only choose to take a Bayesian kind of gamble and decide to gamble on the foundational belief that this is so. I prefer this belief as a starting point over any alternative beliefs that portray the universe as being run under laws that are capricious and unpredictable. Science has had so many shining successes that, even if I can't be assured that its findings and theories are infallible, I choose to heed what scientists have to say. That choice, for me, is just a smart Bayesian gamble, preferable to any of the superstitious alternatives. Or as Robert Frost said:  

                                  Two roads diverged in a wood, and I,

                                  I took the one less traveled by,
                                  And that has made all the difference. 

                  

         

There is even evidence which tells us that the superstitious tribes of the past knew of the inductive method and gained knowledge by it. (2.) (3.) (4.) They only turned to their gods when they couldn’t figure out how some natural process worked. One of the big effects of Science has been to gradually dispel more and more superstitions as better insights into the workings of physical reality are acquired. In fact, most people today, at least in the West, concede almost automatically that superstitions do need to be dispelled. Plagues aren’t caused by evil spirits or God's punishment, and they don’t go away if we burn an incense stick or chant for days at a time. But if we control the rats, we can control bubonic plague. And, in another example, if we selectively breed our livestock, then our chickens, cows, sheep, and pigs keep giving more eggs, milk, wool, and meat. In short, humans everywhere and for a long time have been gradually becoming more and more rational.   

My model of cultural evolution further showed me why it is that some superstitious beliefs hang on for generations before they are dispelled. But in the end, as old thinkers are replaced by more enlightened ones, the method of human learning, whether it is individual or tribal, is an inductive one. We get ideas about the material world and we test them. With giant ones like worldviews or moral systems, we sometimes test them over generations and what we learn is absorbed by the whole tribe over generations, rather than cognized by any one individual. But our knowledge keeps growing, as it must if we are to survive. We are the only concept-driven species that we have, so far, encountered. The knowledge-building, social way of surviving is the human way. Our genetically acquired assets (speed, strength, etc.) are trivial by comparison. We live by learning or we die.