Book Review: The Logic of Scientific Discovery by Karl Popper

I bought this book back in the spring, but had hesitated to read it. The reason for that is I found it quite intimidating, given the thickness of the spine. I will admit that the philosophy of science is something I have dabbled in only as an interested amateur though, of course, years of scientific training and discussions as a student have enabled me to reach (if you will allow me a moment of immodesty) a reasonably sophisticated understanding of my own view of science. Now, though, it seemed appropriate that I ought to look at what others have said.

Before reading this, I was aware that Popper’s views are not universally accepted and that he shared something of a professional rivalry with Bertrand Russell. Also, as a Christian, I find it interesting that I have seen Popper referenced far more by Christian scientists, whereas Russell tends to be more favoured by atheistic scientists. Of course, this is only a trend and there are exceptions. While Russell was a well-known opponent of Christianity, I was keen to learn more about what it is in their competing philosophies that has appealed to the different sets of scientists. So, of course, I will be following this up with some reading from Russell at some point, though if you have any good suggestions as to where to begin, I would be very grateful.

The book begins in a surprisingly accessible manner. I was expected some very high level philosophy that would be difficult to understand, but the translation is very easy to follow. Where he gets a little more obscure, he brings it back down-to-earth with examples that help to put his argument in context. I would describe the argument that Popper creates as being cumulative; that is, there are lots of references to earlier sections and, in particular, definitions. So you have to concentrate or else you can find yourself reading about “singular statements” and not know what he’s talking about if you haven’t followed it earlier.

For this reason, I would not recommend reading this book over a long period of time. I think it demands to be read quite intensively in as short a time as possible in order to ensure that one may follow it all.

The main thrust of Popper’s argument is to say that theories are never verified, they can only be falsified. He dismantles the positivist point of view which led to empiricism and shows that empiricism reduces to mere psychologism. From here, he then needs to discuss the degree of falsifiability. He considers a theory to be less likely the more ways it can possibly falsified. From here, what I think he should have done would then be to talk about corroboration and how a theory stands up to attempts to falsify it. Unfortunately, he leaves this to the end and instead goes off on a rather long and tortuous tangent talking about probability.

This quite long section was the downside for me, as his discussion (and in particular, notation) was quite obscurantist, making it difficult to follow and quite oblique. From here, he moves on to talk about quantum mechanics and in particular the Heisenberg Uncertainty Principle. It has to be noted that this was written during the years that quantum theory was still being formed and, having a background in quantum mechanics myself, I found many of his ideas to be simply wrong. They are a noble attempt at getting to grips with quantum mechanics but ultimately, they have not stood up to subsequent theory and experiments. So in a weird twist, you could say that his argument in this aspect has been falsified.

This brings me to my last point. If his theory is to be thought of as a scientific theory at all, then it must play by its own rules. That is to say, there must be a set of singular statements from this theory that can, in principle at least, be subject to testing to see if they can be falsified. Such a set of statements is not presented to the reader, so I could only conclude that while Popper’s contribution is to be valued and considered, it doesn’t constitute a scientific theory. It remains an application of metaphysics.