In the Synopsis to the Meditations Descartes assures us that ‘extensive doubt… [provides] the easiest route by which the mind may be led away from the senses’ (12). And in the Fifth Replies Descartes adds that it is essential to a proper understanding of the Meditations that ‘the entire testimony of the senses should be regarded as uncertain and even as false’ (350). But to deny our ordinary trust in the senses on the grounds of such ‘hyperbolic’ or ‘metaphysical’ doubts as that one might be dreaming or the victim of an evil demon is, as Descartes himself puts it, quite mad: ‘no sane person has ever seriously doubted that there really is a world and that human beings have bodies’ (16). We seem, then, to be confronted with a dilemma: on the one hand, the skepticism about the senses that we find in the First Meditation must be taken seriously. On the other hand, it is, in some sense, a sham. How, then, are we to understand these doubts?

It is unclear in the Groundwork exactly what Kant takes to be necessary for an act to be morally good or worthy. Traditionally it has been thought that for Kant there are two conditions: it is 1) done in accord with duty, or the moral law, and 2) done for the sake of duty alone. The second condition is commonly thought to entail that an act is not morally good if the agent has a ‘supporting inclination’ or desire to do what is right — be it an inclination of self-interest, or one stemming from some emotion of ‘fellow feeling,’ such as sympathy, compassion, or love. Recent Interpreters, however, claim that Kant is not so strict, because for him the mere presence of a supporting inclination does not necessarily impugn the moral goodness of a dutiful act.

Near the end of the long and often convoluted discussion of freedom in the chapter ‘Of Power’ in An Essay concerning Human Understanding, Locke states that in ‘The care of ourselves, that we mistake not imaginary for real happiness, is the necessary foundation of our liberty’ (E 266). He goes on to explain that ‘we are by the necessity of preferring and pursuing true happiness as our greatest good, obliged to suspend the satisfaction of our desire in particular cases’ (E 266). Locke then adds that the ability to suspend our desires in particular cases is ‘the hinge on which turns the liberty of intellectual Beings’ (E 266).

It is a common antirealist strategy to reject realism about some domain of entities for broadly epistemological reasons. When this strategy is applied to realism about moral facts, it takes something like the following form:

In numerous essays over the years, and most recently in his Meaning, Paul Horwich has worked to articulate and defend a version of the use theory of meaning. At the heart of his project is the idea that the meaning of a word is constituted by a regularity in speakers’ use of it — i.e., by a regularity in speakers’ dispositions to accept as true, to reject as false, or neither to accept nor to reject sentences containing it. A ‘use regularity,’ thus construed, is a dispositional acceptance property distinctive of a particular word and, derivatively, of sentences containing the word.