Scientism is the belief that only scientific knowledge is valid. Thus, it is thought that everything that is true can, at least in principle, be proved by scientific means.
John Cowburn argues that scientism has become too prevalent among scientists and is applied to fields of study where it is not logically applicable. This tendency to try to submit everything to scientific analysis in the attempt to provide a complete system of explanation seems to have been stimulated by discoveries in physics aided by the devising of new mathematical techniques.
It needs to be recognised, though, that there are theoretical physicists and practical physicists. The theorists construct mathematical models which suggest that there are unknown forces or subatomic particles waiting to be discovered, and suitable experiments are devised by practical physicists to test their ideas. These scientists are well aware, of course, that failure to confirm a theory can be caused by faulty equipment or inaccurate measurements as well as invalid theories.
Of course, even those who think that science could, in theory, eventually explain everything are aware that this is not possible in practice. I suspect that what Cowburn is getting at is the tendency of some scientists not to make sufficient distinctions between facts and values.
Early in the twentieth century an increasing number of philosophers wanted their subject to be associated with mathematics and science, rather than the arts. For example, Bertrand Russell had the ambition to solve philosophical problems in the same way that scientific problems, such as those of physics, were solved.
In the 1920s some philosophers in Vienna formed a group which eventually became known as the Vienna Circle. The form of philosophy which they agreed on was called Logical Positivism. This was based on the verifiability principle, according to which all propositions are analytic (usually meaning that they can be shown to be tautologies), or synthetic, which need to be empirically verifiable. Those which could not be empirically verified were said to be meaningless.
Belief in Logical Positivism was eventually somewhat weakened by philosophers who pointed out that the verification principle was not analytic and was not empirically verifiable, and thus was itself meaningless.
A major theme in this book is discussion of free will, presenting arguments to refute those who insist that it is a delusion and that all our actions are matters of cause and effect, over which we have no real control. Obviously, this is an important subject, for if we have no free will we cannot rationally be held to be responsible for our actions. This would mean that a person could not help committing a crime, and if he was caught the authorities would have no choice but to impose the appropriate punishment. Without free will, life would surely be just a meaningless charade, and we would, in effect, be merely robots.
One strong argument in favour of the reality of free will I could not find in this book is that we usually think of free will as being associated with effort. If people achieve success in any field by overcoming great difficulties we say that they have will power.
In his discussion on the Vienna Circle, Cowburn notes that Ludwig Wittgenstein was in Vienna at the time it was formed, but he was not a member, and refers to Wittgenstein's insistence to Cambridge students that philosophers are tempted to "ask and answer questions in the way that science does", quoting from a book by Ray Monk (Ludwig Wittgenstein: The Duty of Genius, Jonathan Cape, London, 1990). In this book, Monk also notes that Wittgenstein denied the necessity to have reasons for religious belief.
As Cowburn is a Jesuit, I expected his chapter on religion would be the most interesting, but I was disappointed that he seems to devote too much space to describing some of the more unorthodox versions of Christianity and secular alternatives to religion. Unsurprisingly, though, he praises fellow Jesuit Pierre Teilhard de Chardin, whose reinterpretations of Catholic doctrine caused much controversy, but eventually helped to persuade many that science and religion were not incompatible.
Other subjects dealt with in this fairly short book, which appears, judging by its style, to be based on a series of lecture notes, include psychology, criminal justice and eugenics. I expect that some readers will feel inclined to explore some of the subjects discussed in greater depth. -- John Harney