This paper develops a dynamic extension of Riker-style heresthetics, the art of winning by restructuring the decision situation rather than by changing anyone's preferences. Classical heresthetics explains how a current loser can be made a current winner by controlling the agenda, the order of votes, the dimensionality of comparison, or the default. The new channel introduced here is that omission changes future availability. Voters have fixed preferences and a social choice rule selects from whatever agenda is offered at each date, but every alternative is supported by a feasibility substrate: the coalition organization, candidate pipeline, legal standing, institutional memory, public salience, professional competence, or interoperability that keeps the alternative practically available. When an omitted alternative's substrate decays below a threshold, the alternative leaves the feasible set entirely. The static heresthetician controls the map from current agenda to current outcome; the dynamic heresthetician controls the composed map from current agenda to current outcome to future feasibility state to future agenda set. The second arrow is the contribution, and it converts agenda power from a selection technology into a feasibility technology. The paper positions itself explicitly as a framework-plus-identification contribution with deliberately narrow one-sided and two-sided maintenance benchmarks, not a full equilibrium theory of lobbying, litigation, or agenda bargaining. The implementation half is built from transparent threshold-crossing arguments whose purpose is to isolate the mechanism and mark its exact boundary. The baseline theorem shows that an agenda setter can install a target that would lose under the initial full agenda by repeatedly offering it against a weaker protected default while withholding stronger rivals until their substrates decay past threshold, at which point the target is not merely the winner of a restricted agenda but the defended winner of the entire surviving feasible set, where "defended" means survival of a simultaneous comparison against everything still feasible rather than a transient win. For Condorcet-consistent rules under linear omission decay the boundary is exact and depends only on what is protected: an initially feasible target is implementable as the defended terminal outcome if and only if no protected alternative defeats it. The paper is scrupulous about the guardrails on this result. A universal-implementation corollary states that the dramatic reading, that a dynamic heresthetician can install anything, is a genuine theorem only over the initially feasible domain and only when the protected set imposes no dominance, and it frames this as the feasibility-side counterpart of McKelvey-Schofield richness, with protection playing the role that a core plays in the spatial model. Companion results show that fixed feasibility would instead force the Condorcet winner, separating the mechanism from cycling-based agenda power; that omission is robust to sophisticated voting, since ballots over offered alternatives cannot maintain an alternative the setter never offers; and that a positive exclusion time is necessary under the linear law. Because the unopposed baseline assumes omitted alternatives have no champion, the paper adds an opponent-maintenance extension. If a blocker's coalition can offset omission decay, the blocker becomes effectively protected, and the characterization generalizes by replacing the protected set with the protected-plus-maintainable set. This layer is developed through a maintenance threshold for an omitted blocker, a maintenance equilibrium under a geometric audit, a two-sided war-of-attrition benchmark between setter and maintainer, and comparative statics, culminating in an opposed characterization theorem. These maintenance results are offered as bounded benchmarks that locate where outside actors can and cannot keep a rival alive, not as a complete game theory of agenda contestation. The identification half is the paper's main contribution. A passive non-identification theorem proves that for any finite passive record generated by a dynamic heresthetic environment whose foreclosed blockers never appear in the record, there exists a benign benchmark, in which those blockers were simply never available or decayed exogenously, that generates an identical record. No passive audit can therefore distinguish heresthetic foreclosure from benign non-availability, and a data set can pass every revealed-preference test over observed agendas while remaining fully consistent with the foreclosure of initially feasible alternatives. The paper is careful that this is not an anti-rational-choice claim: revealed preference over realized menus correctly identifies behavior over realized menus, but it cannot identify the history by which those menus became the feasible menus. The result is positioned as a member of the Austen-Smith observational-equivalence family, but along a different dimension, since the hidden object is the provenance of feasibility rather than the sincere-versus-sophisticated voting strategy. A sharper two-model equivalence makes the point concrete: an omitted feasible alternative and an unavailable alternative are observationally identical to any audit that never probes them. Detection therefore requires stepping outside the realized agenda. The paper defines counterfactual agenda probes and gives a hitting condition under which a probe reveals foreclosure, a pairwise-majority special case, and an audit-rank formulation that quantifies how many probes a decisive audit must run. It then proves an audit-deadline theorem: there is a last feasible date beyond which the decisive counterfactual agenda can no longer be run or credibly reconstructed without restoring the substrate. The deadline is not a claim that preference surveys become impossible, since voters can still report hypothetical rankings after a blocker has decayed; what disappears is the ability to execute or credibly reconstruct the decisive feasible agenda. Restoration authority is defined as the alternative remedy. On the design side, a viability-right impossibility theorem shows that an institution which conditions only on choices over current menus cannot be simultaneously permissive, allowing genuine agenda change, and foreclosure-complete, catching every foreclosure, so that anti-foreclosure protection provably requires non-passive information. Extensions cover stochastic substrate dynamics with high-probability foreclosure under bounded noise, endogenous and critical decay rates, multiple agenda setters, and strategic nomination costs, and the paper closes with applications, empirical diagnostics including a crossed demand-and-availability shock design, an explicit static-versus-dynamic comparison, and a checklist for empirical use.
K. Fathi (Tue,) studied this question.