SEP 2-03 – The Unity of Science

Link: https://plato.stanford.edu/entries/scientific-unity/

Title: The Unity of Science

Author: Jordi Cat

Date: Published on August 9^th 2007, last revision on August 16^th 2017

Expectation: Why this topic?

That all science is connected in some form of unity sounds, at first glance, desirable and appealing to me. Unity sounds like harmony or alliance, both of which have positive connotations. What could unity possibly imply in the context of a variety of scientific disciplines and approaches? It could mean that there is something like a minimal foundation of methodology that distinguishes scientific epistemic agency from any other agency. Especially, the self-critical and self-scrutinizing sciences stand united against the gullible attitude of those susceptible for ideologies and religious convictions. It could also mean that all scientific disciplines, after all, are unified in their explanatory foundations. If this is the case, the unity of science is strongly linked to the previous topic, scientific reduction, and the movement of monism in the sciences: the unity of the sciences is constituted in there being one overarching theory describing the one correct essence or substance of what there is (for example, matter behaving according to universal laws). While the methodological-epistemological unity approach makes sense to me, this metaphysical-ontological understanding does not. Perhaps, there is a third idea, a normative one: The goals and ends of all scientific activity is the same: Knowledge acquisition for the greater good, and advancement of life quality through a better comprehension of the world, and an enabling of sustainable and beneficial human agency. Unity, then, could mean a pulling in the same direction of all sciences towards an improvement of the human condition. But maybe all this is nonsense. Prof. Cat will surely enlighten my superficial and mistaken ideas about scientific unity.

Summary

Cat presents the questions that can be asked concerning a possible unity of science(s) in the introductory abstract of the article:

• Is there one privileged, most basic or fundamental concept or kind of thing, and if not, how are the different concepts or kinds of things in the universe related?
• Can the various natural sciences be unified into a single overarching theory, and can theories within a single science be unified?
• Are theories or models the relevant connected units? What other connected or connecting units are there?
• Does the unification of these parts of science involve only matters of fact or are matters of value involved as well?
• What about matters of method, material, institutional, ethical and other aspects of intellectual cooperation?
• What kinds of unity, not just units, in the sciences are there? And is the relation of unification one of reduction, translation, explanation, logical inference, collaboration or something else?
• What roles can unification play in scientific practices, their development, application and evaluation?

This survey outlines that content and structure of the main body of the article. It starts with a historical overview of the philosophical discussion of unity in scientific agency from the pre-Socratic Greeks to today. The Ancient Greek maintained that the various different sciences and their approaches rest on one metaphysical foundation that provides knowledge of the underlying kind. Christian monotheism endorsed the view that all sciences study the creation of God. Attempts to organize knowledge into encyclopedias in God’s universal language suggest a unity of sciences in such terms. In the late 16^th century this universal language was held to be mathematics and logic symbols. Descartes and Leibniz gave this tradition a rationalist twist that was centered on the powers of human reason and the ideal of system of knowledge, on a foundation of rational principles. By contrast, while sharing a model of geometric axiomatic structure of knowledge, Newton’s project of natural philosophy was meant to be autonomous from a system of philosophy and, in the new context of empirical reasoning, endorsed values of formal synthesis and ontological simplicity.

The Enlightenment tradition in Germany culminated in Kant’s critical philosophy. For him, the unity of science is not the reflection of a unity found in nature, or, even less, assumed in a real world behind the apparent phenomena. Rather, it has its foundations in the unifying a priori character or function of concepts, principles and of Reason itself. Nature is precisely our experience of the world under the universal laws that include some such concepts. And science, as a system of knowledge, is “a whole of cognition ordered according to principles”, and the principles on which proper science is grounded are a priori. Kant had established the basis for the famous distinction between the natural sciences (Naturwissenschaften) and the cultural, or social, sciences (Geisteswissenschaften, or Kulturwissenschaften) popularized in theory of science by Wilhelm Dilthey and Wilhelm Windelband who debated over how differences in subject matter between the two kinds of sciences forced a distinctive difference between their respective methods.

The early 20^th century was much influenced by the German Weltbild tradition, with Max Planck, Ernst Mach, and Wilhelm Ostwald as prominent figures. They endorsed, in different ways, a unity of science (and knowledge) that goes beyond the scientific microworld itself but tries to identify monistic principles that govern all human agency. In the 20th century the unity of science became a distinctive theme of the scientific philosophy of logical empiricism. Logical empiricists—known controversially also as logical positivists—and most notably the founding members of the Vienna Circle in their Manifesto adopted the Machian banner of “unity of science without metaphysics”, a normative criterion of unity with a role in social reform based on the demarcation between science and metaphysics: the unity of method and language that included all the sciences, natural and social.

Cat goes on by introducing the varieties of unity as observed in contemporary debates on this topic:

• Connective and reductive unity: Diversity or hierarchy?
• Synchronic and diachronic unity: Ahistorical or asymmetric temporal/causal relations?
• Ontological and epistemological unity
• Vertical/inter-level and horizontal/intra-level unity
• Global and local unity

The most prominent epistemological unity concept in the context of science is reduction (and its counterview, antireductionism), as discussed in greater detail in the previous SEP entry of this reading project. Unity has been considered an epistemic virtue, with different modes of unification associated with the following roles:

• Demarcation of science from non-science, for example Popper’s anti-metaphysics barrier or Hempel’s deductive-nomological model of explanatory unity.
• Explanation: Rather than modeling unification in terms of explanation, explanation is modeled in terms of unification, for example with cognitive, pragmatist, pluralist or contextualist accounts.
• Methodology (as a principle, not through methodological prescription), for example simplicity or parsimony (unity as an empirical background theory).
• Evidence: A formal probabilistic framework articulates formal characterizations of unity and introduces its role in evaluations of evidence.
• Interdependence and hybridity: the higher-level theories (for example, cell physiology) and the lower-level theories (for example, biochemistry) are ontologically and epistemologically inter-dependent on matters of informational content and evidential relevance; one cannot be developed without the other.
• Conceptual unity: The conceptual dimension of cross-cutting has been developed in connection with the possibility of cross-cutting natural kinds that challenges taxonomical monism. The notion of interfield theories is the idea that unity is interconnection: Fields are unified theoretically and practically. This is an extension of the original modes of unity or identity that single out individual disciplines. Theoretical unification involves conceptual, ontological and explanatory relations. Practical unification involves heuristic dependence, confirmational dependence and methodological integration. The social dimension of the epistemology of scientific disciplines relies on institutional unity. With regard to disciplines as professions, this kind of unity has rested on institutional arrangements such as professional organizations for self-identification and self-regulation, university mechanisms of growth and reproduction through certification, funding and training, and communication and record through journals.
• Material unity (use of instruments and other material objects).
• Graphic unity: Visual representations’ cognitive roles, methodological and rhetorical, include establishing and disseminating facts and their so-called virtual witnessing, revealing empirical relations, testing their fit with available patterns of more abstract theoretical relations (theoretical integration), suggesting new ones, aiding in computations, serving as aesthetic devices, etc.
• Disciplinary unity and collaboration: Unification of disciplines can be interdisciplinary, multidisciplinary, crossdisciplinary and transdisciplinary.

Most discussions of unity of science have been cast in terms of reductions between concepts, the entities they describe, and between theories incorporating the descriptive concepts. Ontological unity is expressed by a preferred set of such ontological units. In terms of concepts featured in preferred descriptions, explanatory or not, reduction endorses taxonomical monism, a privileged set of kinds of things. These privileged kinds are often known as so-called natural kinds. A radical form of ontological unity is eliminativism (for example, neurobiology eliminates and replaces psychology). On the other end of the scale, arguments concerning new concepts such as multiple realizability and supervenience have led to talk of higher-level functionalism, a distinction between type-type and token-token reductions and the examination of its implications. The concepts of emergence, supervenience and downward causation are related metaphysical tools for generating and evaluating proposals about unity and reduction in the sciences.

The opposite of unity—disunity—is endorsed by some, too. The Stanford School understands disunity as a rejection of universalism and uniformity both methodological and metaphysical, but instead as a plurality of unities. Disunity appears characterized by three pluralistic theses: against essentialism, there is always a plurality of classifications of reality into kinds; against reductionism, there exists equal reality and causal efficacy of systems at different levels of description, that is, the microlevel is not causally complete, leaving room for downward causation; and against epistemological monism, there is no single methodology that supports a single criterion of scientificity, nor a universal domain of its applicability, only a plurality of epistemic and non-epistemic virtues. The unitary concept of science should be understood, following the later Wittgenstein, as a family-resemblance concept. Pluralism in this context was characterized by the Minnesota School  in greater detail, distinguishing vertical vs. horizontal, global vs. local, isolationist vs. integrative, and internal vs. external pluralism.

In the last section, Cat reflects shortly on the rationale of unity and what difference it makes. He points out the inherent normative calls in most reflections of unity, for example concerning emergence or interdisciplinarity. They set a standard of what carries the authority and legitimacy of what it is to be scientific. As a result, they make a difference in scientific evaluation, management and application, especially in public domains such as healthcare and economic decision-making. Cat’s very last paragraph reads:

At the end of the day, one should not lose sight of the larger context that sustains problems and projects in most disciplines and practices. We are as free to pursue them as Kant’s dove is free to fly, that is, not without the surrounding air resistance to flap its wings upon and against. Philosophy was once thought to stand for the systematic unity of the sciences. The foundational character of unity became the distinctive project of philosophy, in which conceptual unity played the role of the standard of intelligibility. In addition, the ideal of unity, frequently under the guise of harmony, has long been a standard of aesthetic virtue. Unities and unifications help us meet cognitive and practical demands upon our life as well as cultural demands upon our self-images that are both cosmic and earthly. It is not surprising that talk of the many meanings of unity, namely, fundamental level, unification, system, organization, universality, simplicity, atomism, reduction, harmony, complexity or totality, can bring an urgent grip on our intellectual imagination.

Conclusion and insights

My initial remark that I endorse methodological and epistemological unity of science, especially with the intention of demarcation from non- and pseudo-science, whereas I disagree with the ontological approaches to unity (for example, trying to explain the phenomenon love in physical terms), feels confirmed after reading this article. I am not a monist (even though I once claimed I was).

The by far most interesting part of the article was the reflection on interdisciplinarity and collaboration in section 3.3. This has practical implications for my own research work on technology ethics and normative discourses in innovation contexts. Cat provides many useful references to philosophical work on interdisciplinarity that I will definitely look into. This topic does not have its own SEP entry, so I am glad it is covered here at least a bit. I have always wondered how epistemic agency can work when agents (scientists) with very different microworld-socialisations, languages (or: terminologies), goals, and techniques co-operate. There must be a base level of unity so that different scientists can achieve or create anything useful together.

I copied Cat’s last paragraph into the summary because I am somewhat intrigued by it. Unity’s role is the standard of intelligibility. I don’t buy that. To me, this last comment sounds like “Maybe this unity thing is entire nonsense, but hey, after all, at least, thinking about it makes us exercise our cognitive capacity!”. Maybe we wish there was unity because it is easier for us to grasp the complex mess that the sciences are dealing with, or because aesthetics is more important than epistemic success, after all.

Evaluation and comments on the entry

The entry is comprehensive and covers a wide area of facets of unity in science (history, concepts, fields of philosophical debate and disagreement, applications, and relevance). The text is never too technical or jargon-heavy. Only some paragraphs’ meaning (author’s intent) are not clear to me (in section 3.3, and section 5.3 on metapluralism). All in all, a good survey of the topic.