The greatest thing about science is NOT evidence

 

What is the greatest thing about science? Most people including scientists are quite convinced about the answer to this question. The answer is that science is based on “evidence”. I was no exception to this conviction.

It was until I read David Duetsch. He is a physicist and he is regarded as the father of quantum computers. But his work on philosophy of science is what I am talking about here. He says evidence is still important. But the greatest thing about the science are the theories. In fact evidence itself is theory-laden. Duetsch calls them explanations. The word expalanation is of course familiar to us. He gives a definition to it and he says the greatest thing about science is “good explanations”.

Now what is a good explanation. A good explanation is “falsifiable” and “hard to vary”. At the outset, it did sound like some obsure philosophical idea. Then, as I understand it more, I realize how powerful it is and it is in fact “the thing” that can ensure almost everything good about the human future. What is that? How is good explanation different from bad one?

Consider an example.

Let me take a culturally familar one rather than a core scientific one.

There is a bunch of negative things happening for you in work in a day. Your vehicle is out of fuel at an unexpected time, you are assigned the most difficult project by your boss, your computer socket is burnt, your colleague is unhappy with how you talked with her today and so on. At the end of the day, you will want an explanation. When it comes to examples of bad explanations, astrology for example gives all sorts of bad explanations. In this case, it may give the following explanation. “today its chandrashtamam, bad things will happen, be careful to avoid them as much as possible”. This is a bad explanation. Why? it is not falsifiable and it is easy to vary.

If no bad things happen, its because you were intentially careful or even because of help from some of your good karma. If 4 bad things happen, no matter what sort, then its because of chandrashtamam. If 18 bad things happen still its because of chandrashtamam. You see. This explanation is first of all not falsifiable. A falsifiable explantion has clear, testable predictions about what should happen and what should not happen. If it is contradicted by observation, it must be rejected or revised. The astrological theory here does not provide anything like that. It has no faslsifying aspect to it and it is not testabile. For example, if any number of and even any type of bad things happen, astrology tells that it is because of the chandrashtamam. Then, if none happens the theory should be refuted. But here it can not be refuted, since the explanation also says if you are careful you may avoid problems. You see it is maximally flexible to fit any observations. It cannot be refuted. But don’t think that just because its not refutable it is a great explanation.

Good explanations don’t come like that. They propose a specific mechanism that could in principle be tested. Take the example of your colleague is unhappy with how you talked with her today. A good explanation is, if you have less sleep the last night, then you will have less happy harmones in blood and you will be in bad mood and talk in a dislikable manner to your colleague. This is a good explanation. Why? It can be tested directly. If X is true then Y should not be observed. A statistical data collection over a population on short sleep times, happy harmone levels and the mood on the next day is a good test. If there is a week correlation (observation), less sleep but good mood, then the theory can be rejected. If not then the explanation is accepted. Now it is a good explanation since it has falsifiability. The second aspect is the explanation should be hard to vary. It means, no aspect of the theory can be rejected or selectively accepted to retrofit the observation. You may also see how logically the good explanation is made and it is very specific about the testable parameters to refute it, specific sleep time, harmone level and scale of mood. Astrological explanation doesn’t provide any specific testable parameter like that. Computer not working, Boss gives tough work etc are the observations but explanation was never specific about any of these in the first place in astrology. Astrological explanation is easy to vary. Some part of it can be selectively accepted to fit the observation. They were so broadly vague with no logic and hence they lack any solid predictive power. This is why astrology is pseudo-science.

The scientific explanation doesn’t stay vague. The lack of sleep theory doesn’t unnecessarily venture into computer socket failure. The later must have a separate “good explanation”.

The dangereous thing about astrological explanations are that they are dead ends for knowledge creation. For example, a good explanation for the socket failure is that is wet due to poor maintenance of a waterline. The explanation can be tested. If true then the control actions can be taken and future failures can be predicted. If its chandrashtamam why bother maintenance? There is no room to improve the explanations, predict future and plan course of action.

Still astrological bad explanations are in culture strongly. Why? The reasons are a few. After a bad day you look for answers and that is a cultural or emotional need. This need overrides logic and accepts any answer. The answer comes from easily available astrology. Why astrology came? There is desire to find the reason and control future. Human mind wants to find order among chaos, to see patterns in the world. Pattern recognition is what makes us human, this is the thing we do better than any other animal. But it is error prone. Imagine you were living a few thousands of years ago. You do agriculture and the outcome relies on seasons, good rain means good crop output. This was before any digital entertainment to fill your nights, so stars in the sky are the main things to observe for the curious minds or minds desperate to find order in chaos. Stars and planets seem to move in patterns, the seasons also change in patterns. You connect the two, stars and the rains and your crop output. Eventually you connect every little human concern to the postion of stars and planets mistakenly. Astrology evolves. It eveloves differently in different parts of the world. Astrology is just a relic of such times of human history. Although the set of things that those agricultural socities did and the modern humans do in a day or almost completely different, the astrological theories got  explanatory coexistence in the culture due to their irrefutable nature and vagueness to retrofit any observation.

Thus in astrology the pattern that we mistakenly recognize is the positions of stars and planets in the sky and connect them mistakenly to the complex and detailed concerns of one species of mammals on this one planet. If you apply the pattern recognizing ability without also applying the regourous methods of science to weed out the inherent tendency to error, then the very ability will just see patterns where there are no patterns. This is true even among the well educated who overlook how the things they studied in the school came about.

Knowledge is as Deutsch puts it, information with causal power, specifically "good explanations" that can transform physical objects and solve problems which is exactly what is required for a better future. The observation or evidence is available. But the explanations are the fundamental difference between astrology and scientific explanations.  Therefore, it is not the evidence that is the greatest thing about science but it’s the “good explanations” that are falsifiable and hard-to-vary.