I think everyone should know what the nineteenth-century British biologist Thomas Henry Huxley thought everyone should know, which is that - as he put it - 'science is nothing but trained and organised common sense'. Science is an imperfect, fallible way of exploring the physical universe, but it is the best we have. And it works - which is why we have aeroplanes, the theory of evolution by natural selection, and the miracles of modern medicine.

The 'trained and organised' bit is provided by the scientific method, of formulating and testing hypotheses by experiment. This is something that is not taught explicitly in many undergraduate science courses, let alone taught to non-scientists. And yet a society that fails to appreciate the commonsense nature of science is not only predisposed to undervalue scientific endeavour, but is also more likely to doubt the usefulness of common sense itself. And once that happens, society might as well sit down and give up completely.

Of course, as many people have pointed out, all of that trained and organised common sense often results in discoveries about the world that apparently fly in the face of untrained and disorganised common sense. Albert Einstein's theories of relativity are a spectacular case in point.

See Stuart Blackman's website.