Two of our most successful applications of logic are science and law. Ironically, when the rubber hits the road, both rely on pattern-based reasoning for their most important decisions.
Consider science. We all like to believe that science is an expression of pure logic, that the scientific method insulates science from the irrational aspect of our nature, and that the firmly-established results of science can be proven beyond any doubt.
That’s what we want to believe, and many people do believe. But the fact is, the use of logic is confined to the nuts and bolts of science. All the important decisions in science are made not with logic, but with pattern-based reasoning.
As an example, let’s consider the competition between two theories of the origin of the universe. The first, Big Bang, you surely know about: the universe began its existence confined to an infinitesimal point in space, and then expanded rapidly, eventually spreading out to the density we now observe. But there was another important theory of the origin of the universe: the Steady State theory. In this theory, the expansion of the universe caused new subatomic particles to spontaneously appear at random locations in the universe, constantly creating just enough matter to maintain the overall density of the universe.
Half a century ago, these two theories were in hot competition. The available data did not clearly point in either direction; the choice between the two theories was made on a hunch, and therefore most cosmologists kept an open mind, figuring that new data would eventually clear up the confusion.
And in fact a big discovery did help. The 3 degree Kelvin background radiation, discovered by scientists at Bell Labs, fit perfectly into the Big Bang theory. It didn’t damage the Steady State theory, but it didn’t help, either. This discovery started the process by which cosmologists decided to accept the Big Bang theory.
Note, however, that the 3 degree Kelvin radiation did not in any way prove the Big Bang theory. It comported with it, but it did not by itself constitute irrefutable proof. Yet, as the years went by, the Big Bang theory became the accepted norm, while the Steady State theory was increasingly rejected. It wasn’t until the turn of the century that new data disproved the Steady State theory once and for all. By that time, the theory was already dead; the new data was taken as a historical curiosity, not an important discovery.
Why is it that cosmologists were able to accept the Big Bang theory without proof? The answer lies outside the scientific method: they used pattern-based thinking. When you put together all the available data, it all comports so nicely with the Big Bang theory. The various objections that could be raised against Big Bang were slowly demonstrated to be increasingly improbable. And the detailed theoretical calculations just got better and better at describing the details of the Big Bang. Enough pieces of the puzzle fit together that they hung together nicely, but there were still plenty of holes in the puzzle. There will always be holes in the puzzle -- little details that we can’t fill in yet, but which theoretically could ruin the entire picture if they turn out differently than we expect. Nevertheless, when cosmologists look at the overall pattern of data, calculations, and objections, they conclude -- without proof -- that the Big Bang theory is good enough to commit to.
It’s the same with all scientific theories. They are never proven; they simply accumulate enough supporting data that the scientists familiar with the problem find a good pattern match, and so they accept the theory. Thus, the most fundamental act of science, accepting or rejecting a theory, relies not on logic and proof, but on pattern-based reasoning.
Law functions in the same manner. Sure, we have thousands of volumes of case law that have reduced the practice of law (theoretically) to an exercise in pure logic. But in fact, the most fundamental decision in law is made by means of pattern-based reasoning. I refer, of course, to the decision of the jury in a trial. Each side claims to have proven its case. This is a logical impossibility -- they can’t both be right. The jury must sort through all the evidence and use the overall pattern to reach a verdict. The corpulent body of law surrounding that verdict is all perfectly logical, but when we get down to the fundamental core of the legal system, the jury’s verdict is made by means of pattern-based reasoning, not sequential logic.