Chloé de Canson

Several philosophers have recently drawn on property cluster accounts of natural kinds to argue that individual diseases form natural kinds. According to them, diseases have a super-explanatory property (their pathophysiology) in virtue of which their other properties (their symptomatology, biological signature, response to treatments, and prognosis) tend to co-occur. I argue that we can say more: disease pathophysiologies are mechanisms, such that the property clusters diseases form are homeostatic. I examine the two objections that natural kind theorists have raised against the homeostatic property cluster account, and I argue that they should not deter us from applying it to disease.

What should one believe about the unobserved? My thesis is a collection of four papers, each of which addresses this question. In the first paper, “Why Subjectivism?”, I consider the standing of a position called radical subjective Bayesianism, or subjectivism. The view is composed of two claims—that agents ought to be logically omniscient, and that there is no further norm of rationality—both of which are subject to seemingly conclusive objections. In this paper, I seek, if not to rehabilitate subjectivism, at least to show its critic what is attractive about the position. I show that the critics of subjectivism assume a particular view about justification, which I call the telic view, and that there exist an alternative view, the poric view, on which subjectivism is appealing. I conclude by noting that the tension between telic and poric conceptions of justification might not be an easy one to resolve. In the second paper, “Bayesianism and the Problem of Induction”, I examine and reject the two existing Bayesian takes on Hume’s problem of induction, and propose my own in their stead. In the third paper, “The Nature of Awareness Growth”, I consider the question of how to model an agent who comes to entertain a new proposition about the unobserved. I argue that, contrary to what is typically thought, awareness growth occurs by refinement of the algebra, both on the poric and the telic pictures of Bayesianism. Finally, in the fourth paper, “Objectivity and the Method of Arbitrary Functions”, I consider whether, as is widely believed, a mathematical theorem known as the method of arbitrary functions can establish that it is in virtue of systems’ dynamics that (some) scientific probabilities are objective. I differentiate between three ways in which authors have claimed that dynamics objectivise probabilities (they putatively render them: ontically interpreted, objectively evaluable, and high-level robust); and I argue that the method of arbitrary functions can establish no such claims, thus dampening the hope that constraints in what to believe about the unobserved can emerge from dynamical facts in the world.

I examine Howson’s alluring suggestion that Bayesianism, by supplying a logic of inductive inference—conditionalisation—solves the problem of induction. I draw on his historical heritage, especially Hume, Peirce, and Ramsey, to reconstruct the interpretation of the problem of induction that his remarks intimates. Roughly, it is that of how to amend the system with which one meets the world, in the light of new particulars. Unfortunately, his claim that conditionalisation constitutes a solution to this problem, I argue, fails by his own lights, because it turns on the widely endorsed but nonetheless erroneous contention that a justification of conditionalisation qua rule of inference can be given independently from a justification of the priors.

I present a heretofore untheorised form of lay science, called extitutional science, whereby lay scientists, by virtue of their collective experience, are able to detect errors committed by institutional scientists and attempt to have them corrected. I argue that the epistemic success of institutional science is enhanced to the extent that it takes up this extitutional criticism. Since this uptake does not occur spontaneously, extitutional interference in the conduct of institutional science is required. I make a proposal for how to secure this epistemically beneficial form of lay interference.

We propose an account of the subject’s cognition and its relation to the world that allows for an articulation of the phenomenon of ideology. We argue that ideology is a form of what we call ‘a priori activity’: it transcendentally conditions the intelligibility of thought and practice. But we draw from strands of post-Kantian philosophy of science and social philosophy in repudiating Kant’s view that the a priori is necessary and fixed. Instead, we relativize the a priori: we argue that it is contingent, and therefore revisable. More precisely, it is conditioned materially, in that it is enmeshed with and shaped by material social practice. We conclude with some remarks about the possibility of agency over the relativized, materially conditioned a priori—that is, about the possibility of critique.

Awareness growth—coming to entertain propositions of which one was previously unaware—is a crucial aspect of epistemic thriving. And yet, it is widely believed that orthodox Bayesianism cannot accommodate this phenomenon, since that would require employing supposedly defective catch-all propositions. Orthodox Bayesianism, it is concluded, must be amended. In this paper, I show that this argument fails, and that, on the contrary, the orthodox version of Bayesianism is particularly well-suited to accommodate awareness growth. For it entails what I call the refinement view, which allows us to capture that awareness growth consists in the increase of one’s capacity of discernment.