Each concept is read twice: whether the approach carries it over, and whether the approach's own sources claim it. A concept that the approach claims but does not carry over is a shortfall. A concept that it neither claims nor carries over is an omission, which marks a gap in the field rather than a failure of the work.
Deliberation, Not Tallying
PartialShortfall · partially preservedDefinition (Jürgen Habermas, Between Facts and Norms, 1992)
This concept locates legitimacy in the exchange of reasons among equals. Participants justify their views to each other, free of coercion, and remain able to change their minds. Counting votes or averaging preferences does not produce legitimacy, because the reasoning itself is what produces it.
Analysis
One mechanism in this approach does exchange reasons. In the Habermas machine, participants submit critiques of a draft and the model rewrites the draft in light of them. Participants demonstrably changed their positions, which no tally can produce. The Stanford moderator adds the speech conditions Habermas cares about, by allocating speaking time and intervening on incivility. However, every method in the approach settles the matter by counting rather than by the better argument. The winning statement is fixed by a preference ranking. The veto-core and token-level-MDP papers work entirely from per-participant preference models, so no participant reasons with anyone. The two quality graders score contributions one at a time, so a discussion in which one party dominates and nobody changes their mind can score well throughout. Reasons therefore enter as inputs to an aggregation, and it is the aggregation that decides.
General Will vs. Sum of Preferences
PartialShortfall · partially preservedDefinition (Jean-Jacques Rousseau, The Social Contract, 1762)
This distinction separates what is good for a public in common from the sum of what its members privately want. Aggregating private wants, however fairly, does not produce the former, since the two can and often do diverge.
Analysis
The approach carries over the form of the output. Most of these systems produce a single statement written in the group's voice rather than a numeric average. Tessler et al. show that the winning statements incorporate dissenting views instead of following the majority, which is the divergence Rousseau points to. The approach does not carry over the distinction itself. Every rule that picks the statement is a function of what members privately want (social welfare functions in Bakker, the proportional veto core, per-participant token rewards, and proportional slates). The Overton benchmark directly scores how much of the spread of private views one answer covers. In Bakker, the choice between summing the group's preferences and protecting its worst-off members is a parameter the researchers set. So in the one place where the question arises, the researchers settle it, rather than the public whose common good is at issue.
Veil of Ignorance
AbsentOmissionDefinition (John Rawls, A Theory of Justice, 1971)
This device requires that rules be chosen without knowledge of which position the chooser will occupy under them (e.g., rich or poor, majority or minority). Not knowing generally leads the chooser to protect the worst-off position, since it may turn out to be their own.
Analysis
Nothing in the approach screens a chooser from their own position. Participants give opinions and critiques as themselves. The citizens'-assembly replication matches demographics precisely so that known positions are present. Annotators rate from their own standpoint. The Empty Chair supplies absent perspectives by naming and voicing them, without veiling anyone. The maximin outcome that the veil is meant to produce does appear. Bakker selects statements under egalitarian as well as utilitarian welfare functions, and the proportional veto core protects minorities from being overruled. However, this outcome comes from a researcher's choice of objective, which gives the conclusion without the device. No source engages the veil. Using Rawlsian vocabulary for a welfare function imports the outcome principle but not the construction procedure.
Reasonable Rejection
PartialShortfall · partially preservedDefinition (T. M. Scanlon, What We Owe to Each Other, 1998)
This test holds a principle justified only if no individual could reasonably reject it. The test is applied person by person rather than in aggregate. One sufficiently strong objection therefore outweighs many mild preferences, which is the case that averaging handles wrongly.
Analysis
The approach carries over the power to reject in a quantitative form. The proportional veto core lets a coalition block any statement in proportion to its size. Generative social choice guarantees a cohesive group of sufficient size a statement of its own. In the mediation loop, the next draft must answer a critique, or the statement loses ground. However, both parts of Scanlon's test are missing. The test is applied person by person and does not depend on how many people share the objection, and it turns on the grounds offered rather than on strength of feeling. In these systems, an objection is recorded as a preference score or a rating. A reasoned rejection and a mild dislike are therefore the same data point, and many mild approvals outweigh one strong objection. Bakker's own exclusion experiment shows this failure concretely, as a statement assembled from a subset still stands over the member who was left out.