Noun: The action or habit of estimating something as worthless.

The Popperian view of science is simple-minded enough to be taught in kindergarten. It stems from David Hume’s observation that the future cannot be logically deduced from the past. From this fact, it follows that all scientific theories and laws are mere hypotheses, the truth of which there is no logical ground to accept. Which means that the only certainty we can have about a scientific theory is when it is disproved by experience, in which case, we have firm logical grounds for knowing that it is false.

That is all unquestionably true, but of no practical consequence unless taken seriously, in which case it could be seriously harmful to one’s health. If, after all, you believe that experience is no guide to the future, why not convince your friends by placing a loaded revolver to your head and pulling the trigger?

But there is a perfectly logical argument for accepting that experience is a guide to the future.

If experience were no guide to the future, humanity would face immediate extinction, for in a world where causal relationships as established through experience no longer hold, you car, which was in good working order yesterday, may today, accelerate when you apply the brake and proceed in reverse as you attempt to drive forward. The grocery store may no longer exist, or if it does, the shelves may be stocked with nothing but hardware and rubber boots, or if groceries are still available, a can of beans may be priced in the billions, or all the food may be laced with arsenic, and even if you are able to purchase food and it is wholesome, you digestive system might, nevertheless, turn the contents of your stomach to concrete.

So if you wish to go on living as long and as comfortably as possible, what should you do? There are only two options:

  1. Accept that experience is no guide to the future, and thus like a true deductivist, stay in bed so long as it remains warm and comfortable, rather than attempt to pursue your career or otherwise continue with the struggle for existence.
  2. Contrary to Popperian principles, but in accordance with the 13-billion-year history of the universe, continue with your life on the assumption that the past will continue to be a guide to the future.

Which is the strategy that logically assures you the greatest chance of continued comfort and existence?

There are various ways of tackling this question. But there is no doubt that if you opt for Strategy (1) you are doomed whichever way the world unfolds, whereas if you opt for Strategy (2) there is a chance, however infinitesimally small and logically unsupported it may be, that things will continue merrily on into the future along the lines observed in the past, in which case you may live to see your grandchildren.

So, to act in logical conformity with you desire for continued existence, you are compelled to act on the assumption that past experience will prove to be a guide to the future, which means that you should accept also that, contrary to the Popperian view of the world, Newtonian dynamics will work as well for NASA tomorrow as it did in the days of the Apollo moon landings, and that the equation E = MC2 is sufficiently reliable as a guide to the future that we should go on worrying about Iranian nuclear weapons, and about Israeli nuclear weapons, and about nuclear weapons proliferation in general.

See also: The Scientific Method: Karl Popper’s “small bubble of hot air”