Here is an idea that just might save the world. It is that science, properly understood, provides us with the methodological key to the salvation of humanity.
A version of this idea can be found buried in the works of Karl Popper. Famously, Popper argued that science cannot verify theories, but can only refute them. This sounds very negative, but actually it is not, for science succeeds in making such astonishing progress by subjecting its theories to sustained, ferocious attempted falsification. Every time a scientific theory is refuted by experiment or observation, scientists are forced to try to think up something better, and it is this, according to Popper, which drives science forward.
Popper went on to generalize this falsificationist conception of scientific method to form a notion of rationality, critical rationalism, applicable to all aspects of human life. Falsification becomes the more general idea of criticism. Just as scientists make progress by subjecting their theories to sustained attempted empirical falsification, so too all of us, whatever we may be doing, can best hope to achieve progress by subjecting relevant ideas to sustained, severe criticism. By subjecting our attempts at solving our problems to criticism, we give ourselves the best hope of discovering (when relevant) that our attempted solutions are inadequate or fail, and we are thus compelled to try to think up something better.
By means of judicious use of criticism, in personal, social and political life, we may be able to achieve, in life, progressive success somewhat like the progressive success achieved by science. We can, in this way, in short, learn from scientific progress how to make personal and social progress in life. Science, as I have said, provides the methodological key to our salvation.
I discovered Karl Popper’s work when I was a graduate student doing philosophy at Manchester University, in the early 1960s. As an undergraduate, I was appalled at the triviality, the sterility, of so-called “Oxford philosophy”. This turned its back on all the immense and agonizing problems of the real world – the mysteries and grandeur of the universe, the wonder of our life on earth, the dreadful toll of human suffering – and instead busied itself with the trite activity of analysing the meaning of words. Then I discovered Popper, and breathed a sigh of relief.
Here was a philosopher who, with exemplary intellectual integrity and passion, concerned himself with the profound problems of human existence, and had extraordinarily original and fruitful things to say about them. The problems that had tormented me had in essence, I felt, already been solved.
But then it dawned on me that Popper had failed to solve his fundamental problem – the problem of understanding how science makes progress. In one respect, Popper’s conception of science is highly unorthodox: all scientific knowledge is conjectural; theories are falsified but cannot be verified. But in other respects, Popper’s conception of science is highly orthodox. For Popper, as for most scientists and philosophers, the basic aim of science is knowledge of truth, the basic method being to assess theories with respect to evidence, nothing being accepted as a part of scientific knowledge independently of evidence. This orthodox view – which I came to call standard empiricism – is, I realised, false.
Physicists only ever accept theories that are unified – theories that depict the same laws applying to the range of phenomena to which the theory applies. Endlessly many empirically more successful disunified rivals can always be concocted, but these are always ignored. This means, I realised, that science does make a big, permanent, and highly problematic assumption about the nature of the universe independently of empirical considerations and even, in a sense, in violation of empirical considerations – namely, that the universe is such that all grossly disunified theories are false. Without some such presupposition as this, the whole empirical method of science breaks down.
It occurred to me that Popper, along with most scientists and philosophers, had misidentified the basic aim of science. This is not truth per se. It is rather truth presupposed to be unified, presupposed to be explanatory or comprehensible (unified theories being explanatory). Inherent in the aim of science there is the metaphysical – that is, untestable – assumption that there is some kind of underlying unity in nature. The universe is, in some way, physically comprehensible.
But this assumption is profoundly problematic. We do not know that the universe is comprehensible. This is a conjecture. Even if it is comprehensible, almost certainly it is not comprehensible in the way science presupposes it is today. For good Popperian reasons, this metaphysical assumption must be made explicit within science and subjected to sustained criticism, as an integral part of science, in an attempt to improve it.
The outcome is a new conception of science, and a new kind of science, which I called aim-oriented empiricism. This subjects the aims, and associated methods, of science to sustained critical scrutiny, the aims and methods of science evolving with evolving knowledge. Philosophy of science (the study of the aims and methods of science) becomes an integral, vital part of science itself. And science becomes much more like natural philosophy in the time of Newton, a synthesis of science, methodology, epistemology, metaphysics and philosophy.
The aim of seeking explanatory truth is however a special case of a more general aim, that of seeking valuable truth. And this is sought in order that it be used by people to enrich their lives. In other words, in addition to metaphysical assumptions inherent in the aims of science there are value assumptions, and political assumptions, assumptions about how science should be used in life. These are, if anything, even more problematic than metaphysical assumptions. Here, too, assumptions need to be made explicit and critically assessed, as an integral part of science, in an attempt to improve them.