Harald A. Wiltsche,
Department of Philosophy & Applied Ethics, Linköping University, Sweden
It is a common perception that phenomenology and the broader “continental” strand in modern philosophy is characterized by a distant, and at times, even adversarial attitude towards the exact sciences. However, this perception is increasingly being challenged, if not entirely debunked, in the newer literature. In recent years, for instance, several philosophers with phenomenological leanings have highlighted intriguing links between phenomenology and quantum physics. Philipp Berghofer is one such philosopher.
The starting point of Berghofer’s argument is epistemology, where he defends an internalist, experience-first approach. In this view, “justification-conferring experiences gain their justificatory force by virtue of their distinctive phenomenology”. To illustrate, imagine believing your bike is in the office while you’re in the cafeteria, and then believing your bike is in the office while standing right in front of it. Despite the object of intention being the same in both instances, the phenomenal characters of the two experiences differ. On Berghofer’s view, it is the specific quality of immediate givenness of the intended object that is, epistemologically speaking, fundamental for whether the beliefs we hold are justified.
The idea that the specific quality of an experience is intimately related to the justificatory force it conveys is not inherently implausible. In contemporary “mainstream” epistemology, however, such internalist assumptions often encounter skepticism. Berghofer identifies two primary reasons for this skepticism, both related to physics.
First, there is the argument that modern physics reveals the world of our everyday experiences to be flatly illusory, a stance referred to as objectivism. If objectivism holds true, then an epistemology grounded in simple lifeworld experiences would be as flawed as using basic visual cues to gauge relative object sizes in an Ames Room.
Second, methodological naturalism, a view still prevalent in many areas of modern philosophy, posits that philosophy should adhere to the same methodological directives as core scientific disciplines. Given that the systematic exclusion of all subjective factors is often considered fundamental in this context, an epistemology that favors the first-person perspective appears questionable. The upshot, then, is that internalism seems to conflict with modern science both on methodological grounds and because of its emphasis on simple everyday experiences.
It is at this juncture that Berghofer turns to quantum mechanics to defend his experience-first epistemology. In essence, his argument is that it is not internalism that conflicts with science. Instead, Berghofer contends that it is objectivism and methodological naturalism that contradict quantum mechanics, which is the best-supported and predictively most successful theory humans have ever developed. Hence, Berghofer’s fundamental assertion is that a thorough examination of our most advanced scientific theory should lead one toward internalism, rather than externalism.
To be sure, for quantum mechanics to conflict with objectivism and naturalism, thus supporting Berghofer’s basic claim, it must be interpreted in a specific manner. In this context, Berghofer identifies Steven French’s interpretation of London and Bauer, as well as QBism, as the two most promising options. Despite their differences, both these interpretations reject the notion that the mathematical formalism of quantum physics ought to be seen as a representational vehicle for the “mirroring” of an independently existing physical reality. However, objectivism requires precisely this representationalist assumption. As a result, if we discard a representationalist interpretation of quantum mechanics, the foundation for objectivism also crumbles.
But what about naturalism? In the case of the London and Bauer interpretation, the wavefunction is viewed not as a representation of an external physical reality, but rather as capturing an interrelated system of object, measuring apparatus and observer. However, if the mathematical core of quantum mechanics is understood in this way, then this has far-reaching consequences for methodological naturalism: Given that subjectivity, qua the observer, forms a central part of the mathematical heart of our most robust theory, the call to eradicate all subjective elements does not conform to the spirit of science; it, in fact, contradicts it.
Berghofer’s work is undeniably a valuable addition to the expanding field of phenomenology of science. Instead of getting lost in exegetical shadowboxing—a common problem in contemporary phenomenology—, he maintains a clear argumentative focus, combining the tools of phenomenological analysis with a keen eye on contemporary physics. What is more, considering my extensive collaborations with Berghofer, it will hardly be a revelation to the reader that our viewpoints align on many matters. However, in this brief commentary, I aim to address one critical aspect.
A central theme in Husserl’s late magnum opus, The Crisis of European Sciences, is his claim that modern scientific culture is in a critical state because of the growing chasm between the world as it is allegedly depicted by science and the lifeworld of everyday experience. However, as Husserl emphasizes, the divide between science and the lifeworld is not an inherent consequence of science itself. Instead, it stems from misguided interpretations such as objectivism or naturalism. Overcoming the crisis plaguing modern scientific culture thus necessitates the rejection of the latter.
As far as the rejection of objectivism and naturalism goes, Berghofer’s project perfectly aligns with Husserl’s. However, if Berghofer’s goal is to arrive at an overall position that prevents science and lifeworld from drifting apart, merely rejecting objectivism and naturalism is not enough. The reason for this, as I want to argue now, is the pivotal role that mathematics plays in scientific practice.
The cardinal sin of objectivism lies in the reification of mathematical models and thus in the mistake to take for true reality what is a method. However, for such a mistake to even be possible, model and lifeworld must first be distinct in a manner that then, in a second step, allows for the reification of the former. Allow me to briefly expand on this: To constitute, for instance, the ideal objectivity of a perfectly flat and consequently frictionless plane, we must start on the level of our acquaintance with real surfaces and various techniques to make these surfaces increasingly flat. Then, if we disregard questions of technological realizability, and solely focus on the ideal endpoint of a series of perfectings, we can proceed to successfully constitute a frictionless plane through what Husserl calls an act of idealization.
Although the ideal object still presupposes the lifeworld of real surfaces as its meaning fundament, it is not necessary to always return to the level of the lifeworld to use the ideal object in scientific practice. As we know from out Classical Mechanics introductory courses, we can mathematically describe physical situations, neglecting complicating factors such as air drag or surface friction, without delving into the lifeworld foundations of these idealizations. Husserl refers to this disentanglement of the ideal object from its lifeworld foundation as technization. For science, technization is both a blessing and a curse: On the one hand, it saves us from the need to always return to the primordial level of the lifeworld, thus making the use of idealities much more efficient. But on the other hand, technization is a curse because it harbors the danger of becoming forgetful of the lifeworld foundations on which our idealities rest.
It’s important to be very clear on the relationship between technization and objectivism. One significant distinction is that while objectivism in science presupposes technization, the risk of technization can persist even after objectivism has been rejected. In a forthcoming paper with Arezoo Islami, I argue that this is a real danger unless we pay sufficient attention to the “constitutional archaeology” of the mathematical tools underpinning both our scientific practices and the interpretations of these practices. Let me give a concrete example to illustrate the point.
Since the publication of Tom Ryckman’s masterpiece The Reign of Relativity, we have been cognizant of the phenomenological motives that led Hermann Weyl to reject Riemannian geometry as the mathematical backbone of Einstein’s theory of general relativity. In essence, Weyl found it phenomenologically unsatisfactory that comparing vector lengths across arbitrarily distant points of the space-time manifold required the global availability of externally posited devices such as rigid rods. To eliminate such unfounded idealizations, Weyl introduced his “infinitesimal geometry” (known as Nahfeldgeometrie in German). In this approach, the procedure of length comparison consists in the parallel transportation of a comparison vector in infinitesimal increments along the path between the two vectors. Since the unit of scale (“gauge”) is re-configured at each point of the path, no intuition-transcending auxiliary tools such as rigid rods are necessary.
The Weylean procedure of gauged length comparisons is carried out by an idealized subject that is identified with an arbitrary point in the space-time manifold. During its journey across the manifold, this idealized subject carries along a tangent space, an infinitesimal Euclidean space that surrounds the subject. For the subject, the tangent space holds a privileged status because it is the locus of phenomenological Evidenz. Everything that lies beyond it—such as globally available measuring rods—surpasses the realm of direct, originary givenness and is, consequently, impermissible from a phenomenological standpoint.
As Ryckman has demonstrated, Weyl’s analysis stands as a significant achievement on multiple fronts: In the realm of physics, Weyl’s infinitesimal geometry was instrumental in the formulation of the principle of gauge invariance, giving rise to one of the most prolific concepts in modern physical theory. In phenomenology, Weyl’s analysis represents one of the most radical endeavors to apply phenomenological tools to elucidate the very meaning of the “posit of reality” in modern physics.
However, as impressive as Weyl’s accomplishment is, he does not fully succeed to address all unfounded presuppositions that underlie his account. For example, the concept of the infinitesimal undeniably extends beyond the realm of what concrete Egos encounter in their lifeworld of pre-mathematical experience. Similarly, equating an embodied subject in lived space with an abstract point in a space-time manifold is not without its challenges. While I do not contend that these shortcomings render Weyl’s analysis futile, they do highlight the need for a more radical form of “constitutional archaeology” to bridge the potential divide between the lifeworld and the realm of science.
How do my comments on Weyl relate to Berghofer? While I hold his approach in high regard, I perceive two potential risks: To begin, Berghofer’s argument exhibits a certain tendency to select the interpretation of quantum mechanics that aligns best with his preferred high-level theory in epistemology. While I acknowledge the necessity of starting from phenomenological descriptions to provide the basic tools for our interpretational endeavors, I am cautious about rigidly maintaining a high-level epistemological framework while attempting to understand physical theories. Such an approach may hinder us from learning valuable epistemological insights from physics itself. This would be particularly detrimental in the context of quantum mechanics, as rightly pointed out by figures like London and Bauer, Heisenberg, Bohr, and others. Therefore, I would encourage a more ”hermeneutic” approach that allows for a more flexible oscillation between high-level epistemology and physics without rigidly prioritizing one over the other.
The second critical aspect, which is closer connected to my previous remarks about Weyl, pertains to the issue of technization. One of the central aims of phenomenology is to employ tools like the epoché and reduction to bridge the divide between science and the lifeworld. Berghofer’s commitment to this objective is evident not only through his opposition to objectivism but also in his recognition of the “Lifeworld First!” slogan as a cornerstone of a phenomenological philosophy of quantum mechanics.
However, as I have tried to show, the rejection of objectivism is simply not sufficient for preventing science and lifeworld from drifting apart. Even if we discard the overt reification of mathematical models, it remains a challenge to integrate physical theories like general relativity or quantum mechanics into a phenomenological framework due to their reliance on numerous essential idealizations. This holds true when we represent embodied subjects as points in the space-time manifold or as origins of coordinate systems. However, it also applies when we employ complex numbers, the infinitesimal, Hilbert spaces, or if we associate the wavefunction with the perceptual horizon, as some interpreters of QBism do.
In all of these cases, our anti-objectivism does not shield us from allowing unexamined idealizations to foster a division between science and lifeworld. As I perceive it, the only way to avert this danger is to adopt Husserl’s approach in the Crisis. This entails engaging in thorough, methodical, and historically informed constitutional analyses of the ideal building blocks on which modern scientific practice rests.