Moral rationalists have claimed a priori status for moral principles, including the commonsense principles described in Chapter 4. Intuitionists – prominently including Ross – have even claimed self-evidence for such principles. How can this claim be justified? Central to the case is the idea that normative properties are a priori grounded in certain non-normative natural properties. This chapter explains such grounding. In doing so, it distinguishes two kinds of normativity: a kind belonging to a priori grounds of obligation, e.g. promising – normativity in upshot – and another belonging to propositions, such as moral judgments, that employ normative concepts: this is normativity in content. The chapter shows how the commonsense principles control critical discourse in the constitutive ways appropriate to entrenched a priori generalizations. It also shows how their apriority squares with the empiricality of singular moral judgments and how, even where obligations conflict, singular judgments of overall obligation may be justified and known.

This chapter discusses Aquinas’s account of the freedom of the judgment of choice. It claims that, on his view, this judgment is free because it is up to us whether or not we assent to its propositional content, which Aquinas takes to be a means-end-relating precept. It examines what explains our ability to freely assent to a precept. It argues that this is explained by the logical structure of the precept that the agent assents to. In particular, the precept in question must fail to establish a necessary relation between a given means and the ultimate end. A precept fails to do this if it (1) relates an expedient, but non-necessary means to a non-ultimate end, or (2) a necessary means to a non-ultimate end, or (3) an expedient, but non-necessary means to the ultimate end. It also argues that the logical structure of the precept alone is not enough to guarantee our freedom of assent. An agent must also understand that a precept fails to establish a necessary relation between a means and the ultimate end in order to freely assent to it. To grasp this structure, the agent has to engage in a kind of higher-order judgment.

A crucial methodological recourse in matters of deliberation and inquiry, common sense has a dual bearing. On the positive side, there is a strong pro-presumption that any answers we give to questions of policy and procedure shall incorporate and stand in confirmation with our common-sense beliefs on the matter. On the negative side, there is a strong con-presumption against any rejection or abandonment of common-sense beliefs, and a cogent justification should be provided for any step in this direction. Methodologically, the common-sense approach exerts a strong constraint on our procedures of explanation and validation. This chapter explores how we should think of methodology in common-sense philosophy. Common sense is neither a cognitive faculty nor a way of producing beliefs. A common-sense belief is not produced in a certain way but rather a particular sort of belief, that is, one that is available to people in general on account of its triteness, its palpable obviousness. A common-sense belief is pervasive among the members of a community on the basis of their shared experiences in managing everyday affairs. Common-sense beliefs address matters of everyday run-of-the-mill; they relate to what transpires within the sphere of the ordinary course of things in everyday life.