Current debates about ideal theory and idealization in modern moral and political philosophy do not typically scrutinize the form of reflection itself. This is an unfortunate oversight: assumptions about the form of reflection shape the positions defended in those debates. I argue that the appropriate form of reflection on the nature and justification of standards of justice and morality is the form of practical reason. I further argue that the form of practical reason cannot support many of the idealizations typically deployed in modern moral and political philosophy.

This essay discusses the relation between ideal theory and two forms of political moralism identified by Bernard Williams, structural and enactment views. It argues that ideal theory, at least in the sense Rawls used that term, only makes sense for structural forms of moralism. These theories see their task as describing the constraints that properly apply to political agents and institutions. As a result, they are primarily concerned with norms that govern action. In contrast, many critiques of ideal theory are structured and motivated by their commitment to an enactment model of political theorizing. This instead sees political agents and institutions as instruments for producing or promoting better states of affairs. Enactment models treat the evaluations that rank different states of affairs as justificatorily basic, rather than norms governing action on which structural models focus. This reveals an important feature of debates about ideal theory. Whether ideal theory is capable of appropriately guiding action will depend on what the criteria for appropriately guiding action are, about which different theorists have importantly different views. For example, some popular strategies for defending ideal theory fail, while it may be much less clear that some alternatives to ideal theory can provide action guidance than their advocates claim.

Starting with a particular case of familial care for the aging, the discussion points to the difficulties in deriving practical judgments from ideal theory in cases where there seems to be injustice, but where there are multiple competing dimensions of value and cost. The essay argues that the problems discussed are deeply embedded in modern western cultures, where life expectancy has risen dramatically and has been coupled with a range of other social and demographic changes that make familial care for the aged difficult and burdensome, and where our thinking about justice and rights are integral to the conflicted ways in which people construct and experience these situations, rather than standing independently as a solution to them. The essay argues for a set of partial, limited, and “realist” responses that reduce some elements of burden, without pretending to provide a solution that is in any sense ideal or wholly just. The argument from a case is integral to the essay’s case for realism in moral and political philosophy.

G. A. Cohen famously argued that fundamental normative principles (for example, concerning justice) are “fact-free” in such a way that their truth is independent of non-normative facts. For our purposes here, we take Cohen’s claim as given. Our focus is on what might be thought of as the “other side” of this issue — on whether the non-normative facts that determine what might be feasible for us to accomplish are value-independent. We argue that they are not, that people have reason to think that the normative properties of different possible options can and sometimes do have a crucial impact on their feasibility. In other words: facts about feasibility are partially dependent on Cohen’s “fact-free moral principles.”