From Debate to Deliberation: Structured Collective Reasoning with Typed Epistemic Acts
Organizations: Indian School of Business, India
Abstract
Multi-agent LLM systems increasingly tackle complex reasoning, yet their interaction patterns remain limited to voting, unstructured debate, or pipeline orchestration. None model deliberation: a phased process where differentiated participants exchange typed reasoning moves, preserve disagreements, and converge on accountable outcomes. We introduce Deliberative Collective Intelligence (DCI), specifying four reasoning archetypes, 14 typed epistemic acts, a shared workspace, and DCI-CF, a convergent flow algorithm that guarantees termination with a structured decision packet containing the selected option, residual objections, minority report, and reopen conditions. We evaluate on 45 tasks across seven domains using Gemini 2.5 Flash. On non-routine tasks (n=40), DCI significantly improves over unstructured debate (+0.95, 95% CI [+0.41, +1.54]). DCI excels on hidden-profile tasks requiring perspective integration (9.56, highest of any system on any domain) while failing on routine decisions (5.39), confirming task-dependence. DCI produces 100% structured decision packets and 98% minority reports, artifacts absent from all baselines. However, DCI consumes ~62x single-agent tokens, and single-agent generation outperforms DCI on overall quality. DCI's contribution is not that more agents are better, but that consequential decisions benefit from deliberative structure when process accountability justifies the cost.
Figures & tables
| # | Act | Family | Description |
|---|---|---|---|
| 1 | frame | Orienting | Define how to view the problem |
| 2 | propose | Generative | Put forward a candidate idea or path |
| 3 | clarify | Orienting | Remove ambiguity or distinguish concepts |
| 4 | ask | Critical | Open a useful question |
| 5 | challenge | Critical | Test weakness, assumption, or consequence |
| 6 | extend | Generative | Build on another idea |
| Act Family | Cognitive Function | Failure if Absent |
|---|---|---|
| Orienting | Problem framing | Shallow or misdirected problem definition |
| Generative | Search breadth | Limited option space, premature lock-in |
| Critical | Assumption testing | False agreement, unexamined proposals |
| Integrative | Synthesis | Fragmentation, list of views without judgment |
| Epistemic | Confidence & revision | Fake certainty, no genuine belief update |
| Decisional | Closure | Endless discussion, no actionable outcome |
| System | Overall | Risk ID | Depth | Actionability | |
|---|---|---|---|---|---|
| DCI (Ours) | 45 | 8.24 | 8.84 | 8.62 | 8.96 |
| B1: Single Agent | 45 | 8.84 | 9.42 | 9.00 | 9.00 |
| B3: Simple Voting | 45 | 8.78 | 8.66 | 8.67 | 9.44 |
| B4: Self-Consistency | 45 | 8.65 | 8.37 | 8.53 | 9.32 |
| B2: Unstructured Debate | 45 | 7.75 | 8.39 | 7.72 | 8.76 |
| System | Hidden-Prof. | Late-Evid. | Risk | Disagree. | Policy | Arch. | Routine |
|---|---|---|---|---|---|---|---|
| n=5 | n=5 | n=5 | n=5 | n=10 | n=10 | n=5 | |
| DCI (Ours) | 9.56 | 9.24 | 8.48 | 8.15 | 8.55 | 8.13 | 5.39 |
| Single Agent | 9.25 | 9.60 | 8.85 | 8.87 | 8.82 | 8.73 | 7.88 |
| Voting | 9.30 | 9.26 | 8.03 | 8.68 | 8.26 | 9.19 | 8.86 |
| Self-Consistency | 9.08 | 8.80 | 8.77 | 7.83 | 8.97 | 8.22 | 8.96 |
| Unstr. Debate | 9.03 | 8.45 | 7.83 | 8.24 | 8.03 | 5.78 | 8.58 |
| Metric | DCI | SA | Debate | Voting | SC |
|---|---|---|---|---|---|
| Decision packet | 100% | 1% | 8% | 16% | 0% |
| Minority report | 98% | 0% | 0% | 0% | 0% |
| Reopen conditions | 100% | 0% | 0% | 0% | 0% |
| Explicit assumptions | 3.6 | 3.3 | 0.2 | 0.0 | 0.0 |
| Risk count | 4.3 | 10.5 | 3.5 | 4.9 | 3.4 |
| Objection count | 3.8 | 7.3 | 1.1 | 2.4 | 2.2 |
| System | Mean Tokens | Quality | Quality/kToken |
|---|---|---|---|
| B1: Single Agent | 3,809 | 8.84 | 2.320 |
| B2: Unstructured Debate | 9,458 | 7.75 | 0.819 |
| B4: Self-Consistency | 21,249 | 8.65 | 0.407 |
| B3: Simple Voting | 31,987 | 8.78 | 0.274 |
| DCI (Ours) | 237,565 | 8.24 | 0.035 |
| Condition | Overall | vs. Full |
|---|---|---|
| Full DCI | 8.24 | — |
| A1: No Archetypes | 8.61 0.68 | +0.37 |
| A2: No Typed Grammar | 8.32 1.47 | +0.08 |
| A3: No DCI-CF | 8.33 0.91 | +0.09 |
| Condition | Gemini | GPT-4o | Claude |
|---|---|---|---|
| Voting | 9.24 | 8.73 | 8.66 |
| Single Agent | 9.12 | 8.73 | 8.50 |
| DCI | 8.57 | 8.27 | 8.12 |
| Self-Consistency | 8.50 | 8.75 | 7.62 |
| Unstructured Debate | 6.97 | 8.06 | 7.54 |
Appendix figures & tables1 asset
Supplementary material from the paper’s appendix.
Appendix
| Parameter | Description | Value |
| DCI-CF Parameters | ||
| max_rounds | Maximum deliberation rounds | 2 |
| max_options | Maximum candidate options | 5 |
| finalist_count | Finalists for scoring | 3 |
| convergence_margin | Score dominance threshold | 0.15 |
| fallback_rule | Forced-decision method | outranking |