The Global Debate Evaluation Standard (GDES)
An instrument panel for democratic arguments.
Download the GDES Whitepaper
Explore the full Global Debate Evaluation Standard (GDES) whitepaper for a detailed explanation of the framework, including methodology, scoring philosophy, and version history.
Why we need better tools for evaluating arguments
Democratic debates decide the future of our societies, but the way we evaluate the arguments behind those decisions has barely changed in 2,500 years. We still rely on who sounds confident, who speaks well, and who resonates with our existing beliefs. The result is predictable: the most persuasive argument wins, not necessarily the best one.
GDES is a simple framework that changes this. Instead of judging arguments holistically, it decomposes each one into three measurable dimensions and combines them into a transparent score. Like a cockpit instrument panel for a pilot, it does not make the decision for you — it gives you a clear picture of what you are actually deciding.
Every argument has three dimensions
An argument is not just a claim. It is a claim about a possible future, a reason to care about that future, and evidence that the future will actually come to pass. GDES makes these three components explicit and asks you to score each one from 0 to 10.
Value (V)
How much do we care about what is at stake?
Value captures the importance of the goal the argument appeals to — human life, economic prosperity, freedom, security, fairness. It is the reason the outcome matters in the first place. A high Value score means the stakes are significant; a low Value score means the goal is minor or marginal.
Impact (I)
How large is the difference between the two possible futures?
Impact measures the size of the gap between the future where the proposed action happens and the future where it doesn't. It asks: if the claim is true, how much does it actually change? A policy that reduces emissions by 30% has a larger Impact than one that reduces them by 3%.
Plausibility (P)
How confident can we be that the prediction is correct?
Plausibility measures the quality of the evidence behind the claim. A well-replicated scientific finding scores high. A single unreviewed paper scores low. Plausibility answers the question that persuasion is designed to suppress: how sure can we actually be?
The Formula
Strength = (Value × Impact × Plausibility) / 10 (range: 0–100)
- Zero means zero: If any single dimension scores zero, the entire argument collapses. An argument with enormous impact and deep moral significance but zero plausibility is worthless — it is the vaccine-autism claim or the stolen-election narrative. The multiplication enforces this: you cannot compensate for failure in one dimension by inflating another.
- Proportionality holds: If the value at stake doubles while impact and plausibility remain constant, the argument's strength doubles. A vaccination programme preventing 200,000 hospitalisations produces a stronger Impact score than one preventing 20,000. A meta-analysis of 50 studies is stronger evidence than a single pilot experiment.
- Strong arguments are rare: Because all three dimensions must be high simultaneously to produce a high Strength Index, arguments that are genuinely important, consequential, and well-evidenced are uncommon — and they deserve to stand out when they appear.
A worked example: the Sicilian Expedition, 415 BC
In 415 BC, the Athenian assembly debated whether to send a military expedition to conquer Sicily. Alcibiades argued for invasion; Nicias argued against. The assembly voted for invasion — and lost its fleet, its army, and ultimately its empire. Here is how the debate looks through a GDES instrument panel.
Step 1: Score the pro-invasion case (Alcibiades)
Value: 7
Expanding Athenian power, securing grain supplies, pre-empting a Sicilian alliance with Sparta — substantial but not existential.
Impact: 8
Control of the wealthiest island in the Mediterranean, strategic dominance for a generation — a large gap between the two futures.
Plausibility: 3
Alcibiades' evidence was essentially his own confidence. He had never commanded a major expedition, his knowledge of Sicilian military capability was superficial, and he undersold the difficulty of projecting power across a thousand kilometres of open sea against a city comparable to Athens itself.
Strength = 7 × 8 × 3 / 10 = 16.8
Step 2: Score the anti-invasion case (Nicias)
Value: 7
Athenian security — the same underlying value, just approached from the opposite direction.
Impact: 9
The gap between a future where the expedition failed and a future where the fleet stayed safely in port: losing Athens' fleet, its treasury, and its best soldiers, leaving it vulnerable to Sparta.
Plausibility: 6
Athens was already at war with Sparta. The logistics of a distant campaign were genuinely daunting. The historical record of overextended powers was not encouraging.
Strength = 7 × 9 × 6 / 10 = 37.8
Step 3: Read the instrument panel
Pro-invasion: 16.8 | Anti-invasion: 37.8
The case against is more than twice as strong as the case for. The asymmetry lives entirely in Plausibility: Alcibiades' case rested on confidence, not evidence. In the unscored deliberation, his ethos and the assembly's pathos overwhelmed this gap. The number that should have mattered most — the 3 — was invisible. GDES does not tell the assembly what to decide. It makes legible what the persuasion system concealed.
What GDES does
- Shows which arguments actually carry the debate: Most debates are decided by two or three dominant arguments; the rest is noise. The instrument panel makes the distinction visible between a concentrated case built on strong evidence and a dispersed case built on volume.
- Tells you when the debate is settled — and when it isn't: A 70-vs-25 gap with good evidence on both sides is effectively over. A 42-vs-38 split with low confidence on key dimensions is open, and more evidence could flip it. The current system treats every debate as equally open.
- Makes the cost of opacity visible: When a politician argues without specifying predicted impacts, the instrument panel has empty cells. The absence of a prediction is itself information.
- Transforms disagreement into a research agenda: If an argument has high Value and high Impact but Plausibility of 4, the question becomes precise: what evidence would move it to a 7? This transforms "I don't believe you" into "Here is what would convince me."
- Diagnoses the real source of disagreement: When two scorers diverge, you can see exactly where. If they agree on Value and Impact but differ on Plausibility, the disagreement is about evidence — in principle resolvable. If they agree on Plausibility but differ on Value, the disagreement is about what matters — a fundamentally different kind of conversation.
What GDES does not do
- It does not replace democratic deliberation — it makes it more transparent.
- It does not prevent anyone from raising concerns. Every claim is welcome; the framework only determines what happens after a claim is on the table.
- It does not resolve genuine value disagreements. Some conflicts are about what we fundamentally care about, and democracy must resolve those through voting.
- It does not eliminate bias. It makes bias visible and inspectable, so it can be challenged.
Try it on a real debate
DebateScore.com is the working implementation of GDES. You can score existing debates, compare scores with others, and see how the framework changes what you notice. It is a prototype, designed to be tested and refined. The book and the prototype are not the destination — they are the invitation to build.