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1. What is Philosophy of Science? On the Importance of Philosophy of Science

Published onJun 30, 2022
1. What is Philosophy of Science? On the Importance of Philosophy of Science

What is science?

The central question that philosophers of science ask is: What is science? This question may seem easy to answer at a first glance. The sciences are physics, chemistry, biology, etc., and not music, art and religion. This, of course, is true, but it raises the very same question: What distinguishes those scientific domains and activities from non-scientific domains and activities? What characteristics do the sciences share with each other and not with non-scientific domains? What, in other words, makes science science? (Okasha, 2002).

This question, too, may seem easy to answer. Sciences attempt to explain certain aspects of reality based on observations. But whilst that is certainly not a bad answer, it is not entirely satisfactory. Astrology (horoscopes), too, seeks to explain aspects of reality based on observations, as does religion. So, what is it that demarcates the sciences as science? What is it that distinguishes science from so-called pseudoscience? The latter refers to theories and practices that may appear scientific but are not (such as astrology, creationism, and certain forms of alternative healthcare). Finally, we must also ask what characteristics make science reliable or – in any case – more reliable than pseudoscience. These are the questions we will address and answer in this book.

From the question of what science is, however, follows a series of other questions that philosophers of science ask. What is the relationship between scientific theories and reality? Realists, for example, think that scientific theories represent reality truthfully or, at least that they can represent reality truthfully. Anti-realists disagree. According to the latter, we can only claim that scientific theories can make accurate predictions, not that they actually represent reality (i.e. that they are faithful depictions of the reality they describe).

Another question often asked by philosophers of science is: How do the sciences evolve? Contemporary scientific theories are often quite different from those of, say, the nineteenth century. How did this change come about? According to the philosopher of science Karl Popper (1963) - who will be discussed later – scientific change happens in a gradual way. New theories are typically revisions of previous theories, and we may therefore assume that, in general, the sciences are improving over time. They represent the world more truthfully than the theories they replaced.

Another prominent philosopher of science, Thomas Kuhn (1970), objects. Sciences undergo ‘revolutions’, according to Kuhn, discarding just about everything that came before it. This debate, of course, also has important implications for the question of scientific realism. Someone like Kuhn joins the ranks of the anti-realists because he sees science as an intellectual activity within a so-called paradigm. A paradigm is built on basic assumptions for which there is no evidence. In case of a revolution, one simply discards the old paradigm and starts again in a new paradigm. Therefore, according to Kuhn, the sciences do not come closer to the truth over time, they just switch ways of looking at world (and one way is not inherently more truthful than another way).

You may wonder what use all this is to practicing specific sciences. That is a valid point. The discussion between realists and anti-realists changes little to nothing for the way scientific investigation is conducted. But philosophers of science are not just concerned with science in general, they also think about specific sciences. There is a philosophy of physics, a philosophy of biology, a philosophy of psychology, and a philosophy of economics. In the philosophy of economics, for example, philosophers question whether economic models objectively describe economic reality. Perhaps subjective values creep in? For instance, the value that economists place on freedom (and free entrepreneurship) may lead them to be slightly biased towards perceiving (free) market mechanisms as efficient (and perhaps turn a blind eye to shortcomings of the free market). Or the opposite effect may occur for economists who take moral issue with the inequalities produced by an unregulated market.

This subjectivity, some say, is inevitable because economists – like scientists in any other field – are necessarily selective in what they will measure and represent. We can never represent the economy – with all of its complexity and idiosyncrasies – in its actual entirety, and so we focus on certain aspects and relationships that we (often unconsciously) find important. The same is true in other sciences. Scientists are constantly making choices about what to study, what causal relationships to uncover, etc. The choice of investigating certain features and connections rather than others, comes from value judgments (what scientists believe is important and relevant). Therefore, according to some – contrary to what is often assumed – science can never be completely objective.

Furthermore, philosophers of science who are concerned with a particular science often engage in critical reflection on the assumptions scientists make within their domain. For example, models in classical economics assume that economic agents (consumers and investors) will rationally maximize their "utility" (pleasure, happiness, value). For example, the consumer is assumed to make a rational cost-benefit analysis when faced with the choice of whether or not to buy a good. She will, according to this view, only purchase something when she cannot derive more utility from another purchase for the same price. In recent decades, however, that view of the rational economic actor has been undermined by research in so-called behavioral economics. It turns out that we are not the rational actors that we are assumed to be by the economic models. This has important implications (we will return to this later).

Unlike theories in, say, astrophysics, economic theories - and other theories in the human sciences - have an important impact on our lives. The reason for this is simple: economic theories and models inform economic policy. Misconceptions in the economic sciences lead to mismanagement of society. Some say the responsibility for the global economic crisis of 2008 lies in part with the flawed models that economists created. As a result, banks and other financial institutions considered certain complex financial instruments safe because the models indicated it as such. In retrospect, these models turned out to be widely off mark in their risk assessment. The same is true in psychology and the social sciences. Bad theories lead to bad practices (e.g. in psychotherapy) and bad policies. So, we must permanently question the theories and models we use, as well as the assumptions on which these models are based. After all, our well-being depends on it.

What is philosophy?

This brings me to the question of what exactly philosophy is (and what its purpose is). With regards to that question, there are as many answers as there are philosophers. Answering the question ‘what is philosophy?’, is actually itself a branch of philosophy: the so-called ’philosophy of philosophy’. I will not go into lengthy digressions about philosophy, nor will I give you a precise definition. But it is useful to straighten out a series of misconceptions.

Practicing philosophy does not mean developing obscure theories in an ivory tower. Nor does it involve poetic reflections on the meaning of life. Or at least, it should not. Rather, philosophy is a way of thinking. First, it is a rational way of thinking. In the West, philosophy emerged roughly 2,500 years ago when, for the first time in history, people tried to understand the world without resorting to mythological and religious stories, but by using their own power of understanding. Sciences are also rational, and this is no coincidence: the modern sciences emerged from philosophy. The first modern scientist, Isaac Newton, considered himself a natural philosopher. The father of economics, Adam Smith, was also a philosopher.

Second, philosophy is critical. It takes nothing for granted, but questions everything. Here, it differs in an important way from the sciences. Scientists are also critical and will subject theories to empirical tests before accepting them, but they generally do not question the basic assumptions of their science. Philosophers, however, do. Unlike the sciences, therefore, philosophy is radically critical. It questions the grounds or the foundations (radix is the Latin term for ‘root’) of any theory.

Finally, the reach of philosophy is much broader than that of the individual sciences. The sciences have well-defined domains. Economics, for example, is concerned with the distribution of scarce resources (products and services) in society. Psychology is concerned with human thought and behavior and their underlying mental processes. This is not the case for philosophy. Philosophy does not confine itself to a particular domain. It looks beyond the boundaries of different domains. Doing so, philosophy can develop a different perspective on certain issues. It can freely combine insights from different scientific domains to arrive at new insights. For example, it can combine insights from biology, psychology, economics, sociology, and anthropology to think about how we can best organize society and how we can best address certain social problems. (For the Dutch speaking among you, if you are interested, I attempted to do so in my book ‘De tweede vervreemding’, on globalization and the prospect of global cooperation – Vlerick, 2019).

The importance of philosophy of science

The importance of philosophy in general and of philosophy for the sciences in particular, lies precisely in its reflective and critical approach as well as in its broad scope. In this way it both assists and supplements the sciences. By reflecting on scientific theories, it helps to clarify important scientific concepts. It sheds a critical light on unfounded assumptions in scientific fields. And important findings from the empirical sciences, in turn, are combined and situated in a broader context.

Finally, the philosophy of science is particularly attentive to the processes of the sciences. Too often the emphasis is put only on what the sciences tell us about the world, not on how the sciences arrived at those insights. Philosophy of science accentuates not only what appears on your plate (the ready-made theories), but also what happens in the kitchen (how those theories come about). This is necessary to understand what characterizes science and what makes sciences reliable.

The structure of this book

In a typical philosophy of science course, the question of what science is, is addressed by providing a historical or thematic overview of what prominent philosophers of science have said about it. In this book, however, I take a different approach. I am taking on the question of what science is and what makes it reliable from the perspective of critical thinking instead. By first gaining insight into our own thinking - how our thinking systematically misleads us and how we can improve our thinking - it becomes clear how the scientific context and methodology protect against reasoning errors and generally lead to increasingly reliable theories.

In the next chapter (‘Predictably Irrational’), you will find out exactly what ‘critical thinking’ is, and I will show you, through a series of entertaining riddles, that your spontaneous thinking is misleading in predictable ways. In Chapter 3 (‘Why are we Irrational?’), I will explain why this is the case. In Chapter 4 (‘Irrationality in Action’), I will explain how those reasoning errors lead to certain forms of irrationality, such as superstition, conspiracy theories, pseudoscience, and religion. In Chapter 5 (‘Mastering Critical Thinking’), I will introduce you to the remedy. You will learn how to avoid reasoning errors and how to think (more) critically. In chapter 6 (‘The Importance of Critical Thinking’), I will discuss why this important. Finally, in chapter 7 (‘The Importance and Reliability of Science’), I will link these insights back to the questions with which I started this book, namely: What demarcates science and what makes sciences reliable? In the appendix, you will find material to practice your critical thinking skills. You will find a list of the most important reasoning errors, a series of case studies in which reasoning errors feature for you to detect, and the answers to these case studies. It is best to go over the contents of the appendix after you have read Chapter 2 and before you begin Chapter 3.


What is the central question of the philosophy of science?

‘What is science?’

What questions follow from this central question?

  • What distinguishes science from pseudoscience and from non-scientific fields?

  • What is the relationship between scientific theories and reality?

  • How do the sciences evolve?

What is philosophy?

A way of thinking:

  • Rationally

  • Radically critical

  • With broad scope

What is the importance of philosophy for science?

  • To clarify concepts

  • To critically evaluate assumptions

  • To put findings in a broader context

Further reading

Okasha, S. (2002). Philosophy of science: A very short introduction. Oxford University Press

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