Philosophy of Science 101: The Relationship Between Philosophy and Science

Foreword

The Philosophy of Science series explores both general questions about the nature of science and specific foundational issues related to the individual sciences. When applied to such subject areas, philosophy is particularly good at illuminating our general understanding of the sciences. This 101 series will investigate what kinds of serious—often unanswered—questions a philosophical approach to science exposes through its heuristic lens. This series, more specifically, will look at the ‘Scientific Realism’ debate throughout, which questions the very content of our best scientific theories and models.

Philosophy of Science 101 will be divided into the following chapters:

1. Philosophy of Science 101: The Relationship Between Philosophy and Science

2. Philosophy of Science 101: Scientific Realism

3. Philosophy of Science 101: Anti-Realism

4. Philosophy of Science 101: Realism and Anti-Realism ‘Compromise’

5. Philosophy of Science 101: Causation

6. Philosophy of Science 101: Scientific Models

7. Philosophy of Science 101: Models of Explanation

8. Philosophy of Science 101: Laws of Nature

9. Philosophy of Science 101: Science and Social Context

Philosophy of Science 101: The Relationship Between Philosophy and Science

An Introduction to The Philosophy of Science

The sciences have rich philosophical underpinnings. The philosopher of science, for example, and at the very deepest level, questions if scientific knowledge is possible. If so, how? What methods of reasoning do—or should—scientists use, the philosopher asks. Further, what is the role of observation and experiment in scientific reasoning? Are those theories concerning unobservable entities and processes justified? (Shand & Bird, 2003). This field indeed interconnects with most—if not all—other branches of Philosophy such as epistemology, metaphysics, axiology, and logic, to name a few. The philosophy of science explores scientific theories and "knowledge" in great depth, noting the ampliative nature of such theories (i.e., the kinds of theories that go far beyond what human beings directly observe—a debate around scientific realism). Even if a successful—ampliative—theory is widely accepted as "true", for instance, the philosopher of science might also go on to question (a) what kinds of scientific methods and reasoning can result in its supposed "success" or "truth", and (b) what the very relationship between science and "truth" encompasses. Broadly speaking then, the philosophy of science is concerned with the foundations, methods, and implications of science. The central questions of this study (above) concern what qualifies as science, the reliability of scientific theories, and the ultimate purpose of science (Shand & Bird, 2003).

It must first be noted, however, that philosophers and scientists are not entirely in agreement on the nature of the philosophy of science (Losee, 2010). An example of this lack of agreement is the Stephen Toulmin and Ernest Nagel exchange on whether philosophy of science should be a study of scientific achievement in vivo, or a study of problems of explanation and confirmation as reformulated in the terms of deductive logic. To establish a basis for the subsequent article series, it will thus be helpful to first sketch out the relationship between philosophy and science.

Figure 1: The School of Athens by Raphael (Aristotle and Plato detail), representing the greatest mathematicians, philosophers and scientists (Pulimood, 2022).

Science and Philosophy: Science Needs Philosophy

What is science without philosophy? Unfortunately, there is no straightforward or particularly clear answer to this question. Or at least so the story goes: no answer is genuinely agreed upon, not amongst philosophers, scientists, or even philosophers of science. It is instead much more sensical to consider what philosophy conceptually and practically adds to science. This series of articles is not an attempt to defend philosophy against science, even despite the existing rocky and love-hate relationship. Alternatively, this series is a showcase of the significance philosophy has in science and since the very beginning. This particular article is an introduction to the philosophy of science.

Firstly, it is important to remember that science began via philosophy, tracing back to Plato, Aristotle, and of course Galileo—known as the father of modern science. The main functions of the philosophical foundations of science show just how integral a part philosophy has always been in science from the start, such as in deductive reasoning of axioms, principles, and laws of fundamental scientific theories as additional to their empirical, inductive reasoning. Philosophy provides a conceptual interpretation of scientific knowledge content as a necessary evaluation condition of its attitudinal significance. Unlike general scientific knowledge, the philosophical foundations of science are simply borrowed by science from various branches of philosophy: ontology, gnoseology, social philosophy, axiology, anthropology, and praxeology (Lebedev, 2018). Put differently, science simply cannot do without philosophy since there are so many philosophical stances implicit in the presuppositions and goals of any scientific paradigm and in how theories are connected to reality. As put by De Haro (2019), “It is the task of philosophy of science to critically engage with those presuppositions” (p. 310). Philosophy can have mutual synergy with science, as reflected by the many examples where philosophy is useful for science. Philosophy is not only an integral part of science but can also help advance all scientific enterprise, from theory to experiment. Yet, just like a lion does not have to tell you it is a lion, the prominence of philosophy in science is likewise evident without needing to be spoken of or defended.

Figure 2: Italian astronomer and physicist Galileo Galilei (1564-1642) using a telescope, circa 1620 (Gupta, 2021).

Philosophy in Action

The kinds of heuristic techniques that philosophy brings to science (which may further explore the questions set out in the earlier introduction) are nicely presented in a recent article by philosopher Alan Hájek (2017) in his so called philosophy "tool kit". The tool kit notably shows off common philosophical moves that apply both within and beyond academic philosophy (i.e., to science). Hájek does not offer logic or probability theory (though very useful), but rather presents richer and more common heuristics or "rules of thumb" that often assist philosophers to quickly identify problematic claims or assumptions, an especially crucial skill in science. Several of Hájek’s (2017) tools involve questioning assumptions in the way a claim or question is posed. They also include "evaluation" tools which may apply to a multitude of cases, on top of the invaluable sorts of skills necessary to both strategically and systematically consider alternative possibilities to the conclusions we make via confirmation bias. The point being that when we inevitably fall prey to various cognitive biases that can lead us astray, the philosophy "tools" allows one to resist the tendency to seek and favour evidence that supports—rather than challenges—the hypotheses we (prefer to) believe (Hájek, 2017). Hence philosophy is essential, both in science specifically and life more generally too. This may be illustrated with a few examples taken from various fields of the contemporary life sciences, starting with Stem Cell research.

This first example may show the usefulness of philosophy in science in the sense that philosophy offers conceptual clarification, as presented in Philosopher of Stem Cell and Cancer Biology Lucie Laplane's (PhD) research. Indeed, Laplane (2016) notably finds that the philosophical (conceptual clarification) aspect of science is particularly important since it not only improves the precision and utility of scientific terms but also leads to novel experimental investigations because the choice of a given conceptual framework strongly constrains how experiments are conceived. The definition of stem cells is a prime example, says Laplane. Philosophy has a long tradition of investigating properties. The tools to do this may be applied to describe “stemness” (Laplane et al., 2019, p. 3949), the property that defines stem cells. Philosophy here has helped to discover four different kinds of properties that exist under the guise of stemness in current scientific knowledge. Depending on the type of tissue, stemness can be a categorical property, a dispositional property, a relational property, or a systematic property (Laplane et al., 2019) as a result of philosophical insight. As cited by Laplane et al. (2019), stem cell and cancer researcher Hans Clevers notes that this philosophical analysis highlights “important semantic and conceptual problems in oncology and stem cell biology” (p. 3949). Clevers further suggests that “this analysis is readily applicable to experimentation.” Beyond conceptual clarification, philosophical work in fact has real-world applications as illustrated by the case of cancer stem cells in oncology. Determining the kind of stemness found in each tissue and cancer has become useful to direct the development and choice of anticancer therapies. In practice, this framework has also led to the investigation of cancer therapies that combine the targeting of intrinsic cancer stem cell properties, their microenvironment, and immune checkpoints to cover all possible kinds of stemness (Laplane et al., 2019).

Figure 3: Vector Illustration of Stem Cell (Chebanenko, 2020).

Complementary to its role in conceptual clarification, philosophy can contribute to the critique of scientific assumptions. Philosophy here can even be proactive in formulating novel, testable, and predictive theories that help set new paths for empirical research, as reflected by contemporary research concerning immunogenicity and the microbiome. A philosophical critique of the immune self-nonself framework, for example, has led to two significant scientific contributions. First, it was the basis of the formulation of the discontinuity theory of immunity, a novel theoretical framework (Laplane et al., 2019). According to this theory, the immune system responds to sudden changes in antigenic stimulation and is rendered tolerant by slow or continuous stimulation (Pradeu & Vivier, 2016). This basic yet brilliant principle, which is supported by recent data on immune checkpoints in viral infections, cancers, and allergies, can be seen as a unifying framework for diverse immune responses. As Laplane et al. (2019) writes, this theory “sheds light on many important immunological phenomena, including autoimmune disease, immune responses to tumours, and immunological tolerance to chronically expressed ligands” (p. 3950). The few named empirical assessments illustrate how philosophically inspired proposals may lead to novel experiments, opening up new avenues for research.

Second, the philosophical critique contributed along with other philosophical approaches to the notion that every organism, far from being a genetically homogenous self, is a symbiotic community harbouring and tolerating multiple foreign elements which are recognised but not eliminated by its immune system. This has had far-reaching consequences for our conception of what constitutes an individual organism, which is increasingly conceptualised as a complex ecosystem (Laplane et al., 2019). Inspired by these examples and many others, we see philosophy and science as located on a continuum. Consider Laplane's (2019) proposition:

Philosophy and science share the tools of logic, conceptual analysis, and rigorous argumentation. Yet philosophers can operate these tools with degrees of thoroughness, freedom, and theoretical abstraction that practicing researchers often cannot afford in their daily activities. (p. 3950)

Figure 4: Abstract image illustrating two kinds of self-organising complex systems: a new (philosophical) approach in the debate on biological functions (Sachse, 2020).

Conclusion

Philosophical discussion is genuinely useful to science, as reflected by the above examples of its heuristic approach. The tools—albeit briefly covered—in the philosophical tool kit are of utmost importance to science and shall be explored further in this series of articles. Indeed, the above examples are very far from the only ones. In the life sciences, for instance, philosophical reflection has played an important role also in issues as diverse as evolutionary altruism, debate over units of selection, the predominance of microbes in the biosphere, the definition of the gene, and the critical examination of the concept of innateness (Laplane et al., 2019). Likewise, in physics, fundamental questions such as the definition of time have been enriched by the work of philosophers. David Lewis’ work is a good example of this, which helped to dispel conceptual confusion in physics via his work on closed temporal curves. Philosophical thinking can contribute a great deal to the advancement of science at all levels of the scientific enterprise from theory to experiment as the above examples highlighted. As mentioned, philosophy may also enrich human understanding of fundamental questions surrounding the sciences, such as whether scientists can make genuine theoretical and empirical progress by embracing scientific realism (scientific theories are used to explain and predict observable and unobservable phenomena) or scientific antirealism (scientific theories may not explain observable and unobservable phenomena, nor may they be used to predict "unobservables"). The Scientific Realism debate will be further investigated throughout the series.

Bibliographical References

De Haro, S. (2019). “Science and philosophy: A love–hate relationship,” Foundations of Science, 25(2), pp. 297–314. Available at: https://doi.org/10.1007/s10699-019-09619-2.

Hájek, A. (2017). With the use of heuristics, anybody can think like a philosopher: Aeon essays, Aeon. Edited by S. Dresser. Aeon Magazine. Available at: https://aeon.co/essays/with-the-use-of-heuristics-anybody-can-think-like-a-philosopher (Accessed: December 1, 2022).

Laplane, L. (2016). Cancer stem cells: Philosophy and therapies. Cambridge, MA: Harvard University Press. https://doi.org/10.4159/9780674969582

Laplane, Lucie & Mantovani, Paolo & Adolphs, Ralph & Chang, Hasok & Mantovani, Alberto & McFall-Ngai, Margaret & Rovelli, Carlo & Sober, Elliott & Pradeu, Thomas. (2019). Why science needs philosophy. Proceedings of the National Academy of Sciences of the United States of America. 116.

Lebedev, S. (2018). “Philosophical Foundations of Science: Their structure and functions,” Proceedings of the International Conference on Contemporary Education, Social Sciences and Ecological Studies (CESSES 2018) [Preprint]. Available at: https://doi.org/10.2991/cesses-18.2018.188.

Losee, J. (2010). A historical introduction to the philosophy of science. Oxford: Oxford University Press.

Pradeu, T., & Vivier, E. (2016). The discontinuity theory of immunity. Science immunology, 1(1), AAG0479. https://doi.org/10.1126/sciimmunol.aag0479

Shand, J. and Bird, A. (2003). “Philosophy of Science,” in Fundamentals of Philosophy. 1st edn. London: Routledge.

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