Sander Verhaegh

Scientism, the view that only scientifically supported beliefs are epistemically justified, faces two influential problems: (1) scientism itself does not seem to be scientifically supported and hence self-referentially incoherent; and (2) scientism seems to dismiss many plausible ordinary beliefs as unjustified. In this paper, we show that both problems presuppose a needlessly narrow conception of science and that when scientism is based on a broader, more realistic conception of science neither problem arises. Furthermore, we argue that our variant of scientism is still strong enough to have philosophical bite.

Quine's holistic empiricist account of scientific inquiry can be characterized by three constitutive principles: *noncontradiction*, *universal revisability* and *pragmatic ordering*. We show that these constitutive principles cannot be regarded as statements within a holistic empiricist's scientific theory of the world. This claim is a corollary of our refutation of Katz's [1998, 2002] argument that holistic empiricism suffers from what he calls the Revisability Paradox. According to Katz, Quine's empiricism is incoherent because its constitutive principles cannot themselves be rationally revised. Using Gärdenfors and Makinson's logic of belief revision based on epistemic entrenchment, we argue that Katz wrongly assumes that the constitutive principles are *statements* within a holistic empiricist's theory of the world. Instead, we show that constitutive principles are best seen as *properties* of a holistic empiricist's theory of scientific inquiry and we submit that, without Katz's mistaken assumption, the paradox cannot be formulated. We argue that our perspective on the status of constitutive principles is perfectly in line with Quinean orthodoxy. In conclusion, we compare our findings with van Fraassen's [2002] argument that we should think of empiricism as a stance, rather than as a doctrine.

Quine's argument for a naturalized epistemology is routinely perceived as an argument from despair: traditional epistemology must be abandoned because all attempts to deduce our scientific theories from sense experience have failed. In this paper, I will show that this picture is historically inaccurate and that Quine's argument against first philosophy is considerably stronger and subtler than the standard conception suggests. For Quine, the first philosopher's quest for foundations is inherently incoherent; the very idea of a self-sufficient sense datum language is a mistake, there is no science-independent perspective from which to validate science. I will argue that a great deal of the confusion surrounding Quine's argument is prompted by certain phrases in his seminal ‘Epistemology Naturalized’. Scrutinizing Quine's work both before and after the latter paper provides a better key to understanding his remarkable views about the epistemological relation between theory and evidence.

Some sceptics claim that in cases of peer disagreement, we ought to suspend judgment about the topic of discussion. In this paper, we argue that the sceptic’s conclusions are only correct in some scenarios. We show that the sceptic’s conclusion is built on two premises (the principle of evidential symmetry and the principle of evidentialism) and argue that both premises are incorrect. First, we show that although it is often rational to suspend judgment when an epistemic peer disagrees with you, peer disagreements are not symmetrical. Next, we argue that even if one assumes that peer disagreements are symmetrical, it might still be rational to stick to one’s guns in the light of peer disagreement.