Is science progressing by getting closer to the truth?

Scientific progress has traditionally been regarded as a cumulative process. Scientists such as Karl Popper perceived it as an evolutionary process of uncovering truth in the physical world. This steers us towards the underlying notion of scientific realism which asserts that scientific theories correlate to actual physical “entities and processes”. Thomas Kuhn proposed that the truth-seeking nature of science was to be renounced and replaced by a non-continuous model of scientific progress that was focused on “puzzle-solving”, thereby rejecting scientific realism. One of Kuhn's main successors, Larry Laudan, supported the idea that the key to understanding scientific progress is not an “approximation to truth” but the problem-solving ability of its theories. This essentially leads to an argument in which I will delve into the different views presented by these scientists and provide my opinion towards the notion of scientific progress and its relation to the truth.

Scientific progress can occur in two distinctive ways. One approach of showing that scientific change is progressive is through realism. Rather than arguing that each change involves a rational choice, justifications of realism can be seen as attempts to establish that science is approaching its goal of getting closer to the truth. In contrast, anti-realists argue that science is progressing, not toward truth, but toward greater empirical adequacy. Realists such as Karl Popper regard theories as “attempts to describe reality even beyond the realm of observable regularities, so that theories can be regarded as statements having a truth value” (reference). He proceeds by proposing “verisimilitude” which represents his idea of encompassing truth. Moreover, Popper claims that the predictions that arise from scientific theories can be tested and falsified which will lead to the requirement of a new theory. Popper argues that false theories can also be valuable if they are closer to the truth than their rivals (reference).

Thomas Kuhn's strategy was to avoid the notion of truth and to understand science as a problem-solving activity. Kuhn's main concept lies within the notion of having alternating stable periods in science, in which the primary theories in a particular area of study are accepted by everyone, and transient revolutionary periods in which those theories are scrutinised and are replaced by others. He called the stable periods “normal science” and the revolutionary episodes “revolutionary science”. Normal science is governed by a paradigm. Kuhn distinguishes normal science as “puzzle-solving”, where paradigms determine the parameters for the puzzle and act as the ideal “puzzle-solutions”.
Researchers must then attempt to solve the puzzles by looking for missing pieces and connecting them into a cohesive whole. Normal science is not made to last indefinitely; anomalous experimental and theoretical results will surface which are able to resist the best attempts to resolve them. When anomalities begin to accumulate and push the limits of an accepted paradigm to the point where scientists begin to deem the paradigm untenable, it is considered to be in a “crisis” and the the scientific community must begin to search for alternative paradigms. Kuhn named the shifting or replacement of one paradigm by another a “scientific revolution”. Kuhn himself believes that the model is rather linear than cyclic in nature as it tends to steer science in a new direction instead of returning it to a previous state. The new paradigm should be able to provide us with answers to the anomalities that caused the crisis, and at the same time, preserve much of the puzzle-solving power of its predecessor (reference). Therefore, scientific revolutions are progressive relative to previous work although not toward any final truth about the universe.