Abstract

This paper develops equifelicity as a post-Marxist reconstruction of the Marxian principle of need. The argument proceeds across two formally defined levels whose relation is pragmatic rather than logical. The first level—threshold equifelicity—establishes a lexical constraint: no social arrangement that predictably produces morally inadmissible suffering (S*) can qualify as a system of political justice for those it so harms, because S* destroys the normative addressability that justificatory practice pragmatically presupposes. The modal status of the argument as pragmatic presupposition is explicitly defended and shown to be sufficient for the normative conclusions without any commitment to the view that moral truths depend on justificatory practices—a point that distinguishes the argument's methodological claim from its metaethical neutrality. The second level—needs equifelicity—is derived from an extension of the same argument: stable and reliable participation in justificatory practice across a complete life requires the satisfaction of course-of-life needs, and only need-sensitive distribution can systematically track the individual variation in what such participation requires. Three objections to this inference are addressed: the gap between necessary condition and distributive principle, the empirical specification of required needs-satisfaction, and the slide from sufficientarianism to needs-tracking. S* is operationalized through five diagnostic criteria with a strengthened defence of the type/degree distinction incorporating fuzzy-boundary epistemology and longitudinal evidence. The transcendental argument is defended against non-justificationist objections (Raz, Enoch) through the standing/operative reason distinction and through a methodological/metaethical distinction that shows those objections to operate at a different level than the paper's claims. Scanlonian contractualism is engaged through all three readings, with a new demonstration that the double counterfactual objection applies to the reasons-based version of the prospective-party reading as well as to preference-based versions. New in this revision: institutional case studies (Housing First, unconditional basic income, Nordic welfare); systematic mapping to the capability approach with trade-off resolution criteria; refined responsibility account distinguishing risk-bearing from harm-causing; explicit scope delimitation with global justice research agenda. Keywords: needs; suffering; threshold; justificatory practice; pragmatic presupposition; post-Marxism; capabilities; Lexical Shield; corrosive disadvantage; Scanlon; Forst; Wiggins; responsibility; needs-tracking; normative addressability; fuzzy boundaries; Housing First; global justice