Debating the Bottle Ban: Evidence, Audience and Tone
A Grade 11 student is preparing a five-minute speech for a school debate on the motion: 'This house would ban single-use plastic water bottles on school campuses.' The audience will be students, teachers and two judges. The student's draft opens with a story about a sea turtle, then says: 'Everyone knows plastic is evil. The opposition are either ignorant or paid by big companies. Scientists say 90 per cent of ocean plastic comes from fishing gear, so bottles are not even the problem - wait, no, bottles are the problem. We must ban them immediately.' The draft also includes the line: 'If you care about the planet, you will vote for us.' The student has strong feelings but has not checked the 90 per cent figure, has not explained how a ban would work, and shifts between formal and casual language.
1. Identify one logical problem and one audience problem in the draft. Explain how each weakens the speech.
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Logical problem: self-contradiction. The draft says the 90 per cent figure shows bottles are 'not even the problem', then immediately says bottles are the problem. A debater cannot ask an audience to accept both claims. The contradiction suggests the speaker has not thought through the argument, so the judges are less likely to trust any later evidence.
Audience problem: insulting the opposition. 'Ignorant or paid by big companies' attacks people rather than their arguments. Some listeners may support the motion but dislike the sneer; others may be opposition supporters who are now less willing to listen. The line 'If you care about the planet, you will vote for us' is also a false dilemma: it implies that anyone who disagrees does not care about the planet. That may make the audience defensive rather than persuaded.
Reasoning: a speech succeeds by building credibility with a specific audience. Contradiction damages logos, while insults and guilt appeals damage ethos.
2. Rewrite the opening two sentences after the turtle story so that they state a clear, defensible position for this audience.
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Single-use plastic bottles create a daily waste problem that our school can measure and reduce. A campus ban is a practical first step, not a claim that bottles are the only source of ocean plastic.
Why this works: the position is clear but limited. It does not say plastic is 'evil' or that a ban will solve ocean pollution. It gives the audience a reason to listen - the problem is visible on campus - and it defines the proposal as a first step. That definition also answers the opposition in advance: the speaker is not required to prove that bottles cause most ocean plastic. The tone is formal enough for judges and teachers but still direct enough for students. The turtle story can remain as an attention-grabber, but the argument now rests on a claim the speaker can defend.
3. The student wants to keep the 90 per cent claim. What should she do before using it, and why?
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She should check the source, the date, the definition and the wording before using it. She needs to know who produced the figure, whether it refers to ocean plastic overall or to a particular region or category, and whether it is still current. She should then present it accurately, for example by naming the source and saying what the figure measures.
Why this matters: a debate audience, especially judges, will test evidence. If the figure is challenged and the speaker cannot explain it, the whole case looks unreliable. If the figure is accurate but the speaker uses it to claim that bottles are 'not the problem', she is still misusing it, because a source about fishing gear does not show that bottles are harmless. If she cannot verify the figure, she should drop it or replace it with a claim she can support, such as the amount of bottle waste the school produces in a week.