Introduction

Bas van Fraassen, a leading philosopher of science, was awarded the 2026 Rolf Schock Prize by the Royal Swedish Academy of Sciences “for developing a compelling empiricist account of scientific reasoning that moved decisively beyond logical empiricism, profoundly influenced contemporary philosophy of science and shaped the scientific realism debate” (Kungliga Vetenskapsakademien, 2026). The Schock Prize, established through the will of Dr. Rolf Schock (1933–1986), is one of the most prestigious academic awards in fields lacking Nobel Prizes, recognizing van Fraassen's unique intellectual legacy (Kungliga Vetenskapsakademien, n.d.). Previous laureates—including Quine (1993), Kripke (1997), Dummett (2001), Nagel (2008), and Putnam (2011)—highlight the prize's academic standing. The 2026 award directs attention to the longstanding realism versus anti-realism dispute: whether successful scientific theories provide truthful descriptions of reality's hidden layers or merely serve as efficient predictive tools for observable phenomena (van Fraassen, 1980). Van Fraassen, taking the anti-realist side, offered a novel narrative that revived empiricism and advanced this debate into a new phase (van Fraassen, 1980, 2002). This review traces his intellectual development through key works, concluding with an overview of the connection between his scientific demetaphysicalization and religious beliefs.

Portrait of Van Fraassen: Life, Intellectual Growth, and Evolution of Views

Van Fraassen's entire philosophical activity can be understood under a single "demetaphysicalization of science" project (van Fraassen, 1989, 2002). While taking modern physics seriously, he believes contemporary science bends under the weight of metaphysical interpretations imposed by realists. Just as the Renaissance established science's independence from theology, van Fraassen (1989) argues a second step is now necessary: liberating science from philosophy and metaphysics. His oeuvre represents a comprehensive effort to establish this independence, demonstrating his deep commitment to empiricism. He argues empiricism should not be viewed as a doctrine or set of true beliefs about the world—as turning it into a positive theory would itself fall into metaphysics—but rather as an intellectual and practical stance characterized by continuous critique of metaphysics and reverence for sensory experience (van Fraassen, 2002).

Born in 1941 in the Netherlands, van Fraassen immigrated to Canada in 1956. He completed his doctorate at the University of Pittsburgh under Adolf Grünbaum in 1966, and has taught at Yale, Toronto, and Princeton, currently McCosh Professor of Philosophy, Emeritus at Princeton University (Kungliga Vetenskapsakademien, 2026). His foundational contribution to philosophy of science cannot be understood independently of his formal genius in mathematical logic; precise formal tools he later employed to dismantle metaphysical structures resulted from over a decade of leading research in formal logic (van Fraassen, 1966, 1968, 1971).

Van Fraassen's formal research includes three main achievements. First, he developed supervaluationism to address truth-value gaps in natural and scientific language, preserving classical logic's fundamental principles while accepting gaps in proposition components (van Fraassen, 1966). Second, he developed free logic enabling formal reasoning without existential commitment to terms, avoiding unwanted ontological assumptions (van Fraassen, 1968). Third, in Formal Semantics and Logic (1971), he demonstrated how modal concepts like necessity and possibility could be explained without assuming heavy metaphysics of real parallel worlds. These formal achievements provided the epistemological prerequisite for reconstructing scientific language without conceding to metaphysics.

In the decades before The Scientific Image (1980), logical positivism collapsed under critiques from Popper (1959), Quine (1951), and Kuhn (1962), leaving scientific realism to regain dominance. Van Fraassen proposed constructive empiricism, reviving empiricism and emerging as the most effective challenge to scientific realism (van Fraassen, 1980). He redefined science's aim as empirical adequacy rather than truth—theories need only provide true statements about observable phenomena, without claiming anything about unobservable entities (van Fraassen, 1980, p. 12). He distinguished between accepting a theory for practical purposes and believing in its truth; scientists can accept theories without believing in the objective existence of unobservable entities (van Fraassen, 1980). He argued explanatory power is a pragmatic virtue, not an epistemic one, and critiqued Inference to the Best Explanation through the Bad Lot Argument (van Fraassen, 1989). Unlike instrumentalists, he interprets scientific language literally but restricts belief to empirical adequacy (van Fraassen, 1980). Thus, science becomes a constructive activity of "saving the phenomena" rather than discovering reality's hidden truths (van Fraassen, 1980).

Van Fraassen then addressed the question of laws of nature in Laws and Symmetry (1989). He considers laws a redundant, constructed concept imposing heavy metaphysical burdens (van Fraassen, 1989). He presents three arguments: historically, the concept originated from 17th-century metaphysics rather than physics itself; formally, any law theory faces an irresolvable dilemma between inference and identification; and practically, laws' four supposed functions (explanation, confirmation, necessity interpretation, and understanding science's structure) are all manageable without metaphysical assumptions. He proposes symmetry as a formal and structural replacement, purifying science from additional metaphysical commitments (van Fraassen, 1989). Symmetry is not an objective feature of the external world but a methodological guide in theorizing, enabling scientists to construct models without invoking natural necessities (van Fraassen, 1989).

In Quantum Mechanics: An Empiricist View (1991), van Fraassen applies his framework to quantum interpretation. Drawing on Bell's theorem, he demonstrates quantum phenomena inherently defeat classical causal models. He proposes a modal interpretation separating dynamic state from value state, resolving collapse without metaphysical assumptions (van Fraassen, 1991). Despite challenges in fully resolving the measurement problem, this interpretation provides an empiricist understanding of quantum theory (van Fraassen, 1991).

In The Empirical Stance (2002), van Fraassen redefines empiricism's identity. He argues traditional empiricism formulated as a doctrine about the world is doomed, falling into what he calls Principle Zero—the assumption that every philosophical position equals belief in a specific proposition (van Fraassen, 2002). Rejecting this, he elevates empiricism from a truth-apt doctrine to a stance—a way of living, value commitment, and epistemic policy (van Fraassen, 2002). He turns to voluntarism, drawing on James and Pascal, defining rationality as any logically consistent belief being rationally permitted (van Fraassen, 2002). This approach explains scientific revolutions, where emotions and imagination play crucial roles.

In Scientific Representation: Paradoxes of Perspective (2008), van Fraassen challenges representation based on resemblance. He views representation as use-oriented: a triadic relation where users employ objects to represent something as something, transforming representation from static relation to dynamic, context-dependent action (van Fraassen, 2008). Introducing "data models," he shows representation never occurs directly between theory and world but through layer-cake structures (van Fraassen, 2008). Referring to Hermann Weyl's paradox, he demonstrates mathematical structures lack inherent identity and always require perspectives—a serious blow to structural realism (van Fraassen, 2008). Science provides images seen through human perspective, not copies of objective world structure.

Importantly, van Fraassen's demetaphysicalization is not skepticism but aims to protect the domain of faith and religious experience. He explicitly states empiricism is not scientism and is compatible with religious belief (van Fraassen, 2002). By limiting science to its natural boundaries, he prevents it from becoming an idol and preserves space for religious experience alongside scientific rationality (van Fraassen, 2002).

Conclusion

Van Fraassen, through his bold demetaphysicalization project, created one of the most influential anti-realist alternatives in contemporary philosophy of science (van Fraassen, 1980, 1989, 2002, 2008). By redefining science's aim as empirical adequacy and restricting theory acceptance to belief in that adequacy, he took a fundamental step in reconstructing empiricism and rescuing it from positivist instrumentalism (van Fraassen, 1980). His critique of laws of nature and replacement with symmetry, his modal interpretation of quantum mechanics, his voluntarist epistemology, and his pragmatic theory of representation form links in an intellectual chain leading to a position where science is not a complete mirror of existence but an efficient tool for organizing sensory experience and "saving phenomena" (van Fraassen, 1980, 1989, 1991, 2002, 2008). The 2026 Rolf Schock Prize confirms this project's enduring importance and demonstrates that constructive empiricism, despite all critiques, remains one of the most vibrant approaches in contemporary philosophy of science (Kungliga Vetenskapsakademien, 2026).