Strategy & Weighing 2
Because Parli forbids prepared evidence, debaters substitute well-reasoned logic and common knowledge for citations. You will be able to distinguish strong reasoning-based support from weak, unsupported assertion.
Analogy and historical example
One powerful substitute for a citation is a clear historical or real-world analogy that the judge likely already knows, such as referencing Prohibition when arguing that banning a popular substance drives it underground rather than eliminating it. The key is picking examples specific and well-known enough that the judge can verify them mentally without you having to prove they're true.
First-principles logic
When no analogy fits, debaters build arguments from first principles — basic, widely accepted premises stacked into a chain, like 'people respond to incentives, financial incentives affect institutional behavior, therefore an institution paid per unit of X will try to maximize X.' Each link should be something a reasonable judge would accept without further proof.
Avoiding unfalsifiable assertions
Weak Parli arguments often sound like warrants but are actually just claims dressed up ('this is obviously true because it's common sense'). A real warrant gives the judge a mechanism they could explain back to someone else; an assertion just repeats the conclusion more forcefully.
Preempting the 'source' objection
Sharp Opposition debaters sometimes challenge a Government example by saying 'you have no source for that.' The best response isn't to pretend you have a citation, but to reframe: 'this is a widely known historical event, not a contested statistic, and the judge can weigh it as common knowledge — if you have a specific factual dispute with what happened, raise it, but a general demand for a source in an evidence-free format isn't a real argument.'
The motion is 'This House would legalize all recreational drugs.'
A weak Opposition argument: 'Legalizing drugs is obviously dangerous and bad for society.' That's just a louder claim. A strong version: 'Portugal decriminalized personal drug possession in 2001 and redirected enforcement resources into treatment, and overdose deaths dropped significantly over the following decade — this shows that decriminalization paired with treatment infrastructure works, but Government's model has no such treatment infrastructure attached, so we'd get the risks of legalization without the Portuguese safeguards that made it succeed.' This uses a specific, checkable example and explains the mechanism rather than just asserting danger.
1. Which of these is the strongest substitute for an evidence card in Parli?
2. What is wrong with the argument 'this policy is bad because it's obviously bad'?
3. True or False?
"A good analogy should be specific and well-known enough that a judge can mentally verify it without further proof."
4. How should a debater respond when an opponent says 'you have no source for that' about a well-known historical fact used as an example?
Answer all 4 to check.
Replace evidence cards with specific examples and transparent chains of first-principles logic, never with louder repetition of the claim.