After the 17th century battle of the inductive logic of empiricism and the deductive logic of rationalism was reconciled, a number of new philosophies of science have come and gone through the 18th and 19th centuries, barely able to keep pace with the explosive growth of science they purported to describe. The new battle came to be between Scientific Realism and Critical Empiricism.
First, in the 1920s, a philosophy of Moritz Schlick (1882–1936) and Hans Reichenbach (1891-1953), known as Logical Positivism gained wide popularity. It was an extreme version of Empiricism, with a helping of Positivism of Auguste Comte and the works of Ludwig Wittgenstein. Logical Positivism held that not just the scientific knowledge is based on sensory perception, but, in fact, ALL knowledge was. Only the knowledge that could be verified was declared to have any meaning, stripping theology, metaphysics, and much of philosophy of their regalia. Despite being popular for almost 30 years and dominating the world’s philosophy in the 1950′s, Logical Positivism eventually buckled down under the critique of Ayers, Putnam, Quine, Kuhn, and Popper, among others, and went extinct by 1970.
Scientific Realism is perhaps the most notable successor of Logical Positivism. It is the philosophy that states that the conclusions of science are not tentative (as pragmatists and critical realists say), but, in fact, true, and describe the objective, mind-independent reality, whether we believe in it or not, even if we cannot observe it. It is based on the fact that the scientific progress occurs, and that science is able to both answer more and more questions and to predict more and more phenomena of nature, from which the realists infer that the theories do, in fact, describe the world correctly, or near-correctly. They point out that when a theory is replaced by a new one, it typically incorporates the older theory as a special case, and does not invalidate it or its description of the world, instead it only makes it more precise.
Early proponents of Scientific Realism were generally scientists, such as Plank and Einstein, but, beginning with the 1970s, philosophers started working on fledgling this view into a serious system, able to withstand continuous attacks of numerous anti-realist philosophies, from Empiricism and Phenomenalism to Instrumentalism and Constructivism and Conventionalism and even Feminism. At this time, Scientific Realism is still considerably fragmented, unable to fight on so many fronts at once. The Stanford School of Scientific Realism, represented by Nancy Cartwright (b.1944) and Ian Hacking (b.1936), defends only the so-called entity realism, the view that the invisible entities of science, such as electrons, atoms, force fields, wave functions, are all actually real, while the laws describing them may not be. The ontological side of Scientific Realism, the assertion that scientific laws describe the true reality, is subject to ongoing philosophical battle. Check out my book picks to see what is going on.