Theory of Science

I have been reading Theory of Science: A Short Introduction, by Jonathan Knowles (Tapir Akademisk Forlag, 2006). I found it on the new books shelf of the Engineering and Physical Sciences Library. It has been very interesting so far.

The first chapter discusses Einstein's theory of relativity, quantum mechanics, and logical positivism. Logical positivism was an important step in the philosophy of science, though few accept it completely today. Its most controversial claim was that science = rational belief. If something is not science, it is not rational. (Of course, this philosophical position is completely opposed to the rationality of religious belief or the possibility that we might discover truths in some other way.) Knowles discusses the problems of logical positivism, including its claim that meaningful must be "verifiable," a fuzzy term with multiple interpretations, including those that allow religious and metaphysical statements to be meaningful and those that would make certain universal statements meaningless. Finally, logical positivism does not take into account that observations are affected by previous knowledge and experience.

The second chapter discusses Karl Popper. Popper presented a philosophy of science that is very to the common understanding of the scientific method. Popper argued that science (1) recognizes a theoretical problem, (2) proposes a solution (the hypothesis), (3) tests the hypothesis, and (4) rejects the hypothesis if the evidence contradicts it. Else, we retain the hypothesis, though we can never prove that it is true. Knowles describes an important objection to Popper's philosophy: the complexity of real tests: if we get evidence that contradicts the hypothesis, then perhaps we made some other assumption that is false.

Later in the chapter, Knowles describes the "hypothetico-deductive method" (HDM), which adds induction to Popper's approach. In the HDM, negative evidence doesn't cause us to reject a hypothesis, but it is weakened. Positive evidence strengthens it.

Chapter 3 discusses Thomas Kuhn's history of science as the rise and fall of paradigms. Science is not a smooth accumulation of better theories; it is punctuated by scientific revolutions that replace one paradigm with another. In Chapter 4, the book takes up Imre Lakatos' alternative explanation of science as the progression of research programs. Knowles carefully describes the differences between these and then moves on to other developments in the philosophy of science.