Dynamics of Reason

"This is, in many ways, a tour de force . Friedman repeats the call of Hermann von Helmholtz, who is one of his philosophical heroes: Back to Kant! And while Helmholtz had in mind the excesses of German idealism, Friedman is moved by a deeper reading of logical positivism, which was the scapegoat of Kuhnians and Popperians. This deeper reading is not in essence a reinterpretation, but a rehabilitation. Friedman unveils the Kantian origin of the basic tenets of logical positivism, showing at the same time how they were transformed and redefined in the light of Frege’s and Russell’s new logic, Hilbert’s axiomatic method, and the fundamental changes in physics and geometry in the turn of the twentieth century. On Friedman’s reading, both Kant and the logical positivists shared a common project: showing how the scientific image of the world can yield objective knowledge. Kant found in Newtonian theory a model of how the fundamental laws of nature are founded in universal principles of human knowledge, and especially in the principles of mathematics and Euclidean geometry. These universal and necessary principles of human knowledge the forms of pure intuition provided the framework within which scientific knowledge and objectivity, as exemplified by Newtonian mechanics, are defined and defended. “On Friedman’s reading, both Kant and the logical positivists shared a common project: showing how the scientific image of the world can yield objective knowledge” According to the Kantian conception of knowledge, the possibility of human knowledge presupposes synthetic a priori constraints when building models of the world based on experience. The synthetic a priori principles are universal, necessary, and certain. Being independent from experience, they are unrevisable. At the same time, they constitute the object of knowledge. In a similar fashion, the logical positivists had sought to show how objectivity could be redefined and defended in light of the new, post-Newtonian scientific worldview that was shaped by Einstein’s theory of relativity and quantum physics. The transformation of the very idea of ​​objectivity and the validity of scientific knowledge relied on the thought that the principles of mathematics and logic constitute an a priori scaffolding upon which the empirical knowledge of the world is hooked. Central to this transformation is Hans Reichenbach’s Relativitätstheorie und Erkenntnis apriori , which was published in 1921. In the light of the theory of relativity, which challenged both Newtonian mechanics and the underlying Euclidean geometry, Reichenbach proposed a distinction between two elements of the Kantian conception of synthetic a priori principles: (a) a priori principles are considered unrevisable, thus necessarily true; and (b) a priori principles are considered to be constitutive of the object of knowledge. Reichenbach accepted the second dimension, but denied the first. That is, he denied that a priori principles are necessarily true and unrevisable. Instead, being dependent on a framework, they must be abandoned when the framework they constitute is abandoned. The framework is abandoned for broadly empirical reasons; in particular, when the theories that are embedded in it are in persistent conflict with experience. This new conception of the a priori, qua a set of principles constitutive of a theoretical framework, retains the spirit of the Kantian idea that there can be no systematic attempt to know the world unless the acceptable empirical theories are limited in such a way as to satisfy a set of a priori principles, which describe the basic structure that the world must have in order for it to be knowable. But these a priori principles become at the same time relativised; that is, revisable. This way of viewing things leads Friedman to show that the distinct and autonomous role of philosophy is established not by the fact that it is cut off from science. Rather, the role of philosophy is to provide the (meta-scientific) domain upon which reason is called to unveil and highlight the rationality that permeates, and the continuity which characterizes, the otherwise radical scientific revolutions. In other words, philosophy offers the domain in which the various constitutive a priori principles of the various theoretical frameworks are detected and explained as well as the space in which the reasons for their change become visible. This is what Friedman calls ‘Dynamics of Reason’. “The transformation of the very idea of ​​objectivity and the validity of scientific knowledge relied on the thought that mathematics and logic constitute an a priori scaffolding upon which the empirical knowledge of the world is hooked” The Kuhnian approach to science, from which Friedman takes some cues, oscillates between two fundamentally different and conflicting assumptions: the rationality of normal science and the irrationality of revolutionary change. The synthesis sought by Friedman restores rationality in scientific change within a meta-scientific (and hence philosophical) domain, highlighting the role of constitutive and at the same time revisable principles. But if the constitutive principles are framework dependent and revisable, how is (descriptive) naturalism or scepticism avoided? Friedman’s answer is that philosophy provides a regulative ideal: viewing the succession of theoretical frameworks or paradigms as a convergent series in which “we successively refine our constitutive principles in the direction of ever greater generality and adequacy” (DR, 63). Philosophy and the sciences are in a perpetual relationship of dynamic interaction and mutual determination. The prime philosophical project therefore consists in seeking the “universal, unchanging principles” of reason, as Ernst Cassirer had put it. Kitcher’s approach is a lot more naturalistic and, as of late, pragmatic. Friedman’s approach is anti-naturalistic: he emphasises more the role of human mind in the constitution of the object of knowledge of science. I would single out three (revealing my own preferences and biases). The first is in the metaphysics of science and has to do with the implications of the scientific image for the deep structure of the world. ‘Metaphysics’ is no longer a dirty word. The on-going battle between neo-Humean and neo-Aristotelian conceptions of the world is a case in point. The neo-Aristotelian tradition inflates ontology with causal powers, necessary connections and the like in order to explain and ground the regularity there is in the world, while the neo-Humean tradition takes regularity as a brute fact, does away with regularity-enforcers and advances a metaphysically thin conception of laws of nature. In between, there are the structuralists and the primitivists. I find the engagement with the role of mechanisms in causation, explanation and scientific practice in general particularly promising. “‘Metaphysics’ is no longer a dirty word” The second direction that I consider most interesting has to do, unsurprisingly, with the scientific realism debate. In particular, there are attempts to re-evaluate the role and strength of the historical challenge to realism, to discuss the microstructure of theory-change in science and to develop new forms of anti-realism. Get the weekly Five Books newsletter The third direction has to do with the role of values (both epistemic and social) in science and in science-based policy making. Here I think there is still a lot to be learned. The big challenge is to unveil the role of values in science (in theory-choice, theory-appraisal, and decision-making under uncertainty) while at the same time defending the objectivity of science and scientific knowledge. There is immensely interesting work going on (in relation to issues concerning climate change and other issues) and we have still a lot to learn from feminist perspectives on science, including my own favourite: standpoint epistemology in general, and feminist standpoint in particular. “Feminist approaches to science have played a key role in uncovering various cognitive and social biases and have promoted the image of a socially responsible science” A fourth direction which has attracted my own interest lately is the history of philosophy of science. Apart from its own intrinsic interest, engagement with HoPoS has a lot to teach us about current debates and why they have taken the turns they have. Absolutely! Philosophy offers a magnifying glass through which the invisible causes of certain prejudices, biases, assumptions, or presuppositions are clearly seen and questioned. Science is by far the best way we humans have invented to push back the frontiers of ignorance and error, to achieve a deep understanding of the world and of our place in it, and to make the world a better place to live. But science is not a faultless, value-neutral and interest-free way to understand and change the world. Hence, science needs critical defence against excessive scepticism, relativism and public distrust. “Science needs critical defence against excessive scepticism, relativism, and public distrust” Philosophy can play a critical role in defending the objectivity of science, in showing the robustness of scientific facts and in combating the ‘post-truth’ ideology. Science needs philosophy more than ever. In fact, society at large needs philosophy more than ever. Philosophy is the living example of the tremendous achievements of human reason. It is our collective insurance against, unreason, authoritarianism and conceptual vacua. It is sad that many scientists treat philosophy as an after-retirement pass-time. Philosophy does not merely fill the cracks of the scientific image of the world. It is the glue that holds it together."