The Plastic Bottle Brief

Classification. Canteen sales data is primary if the team or school collected it; it becomes secondary if it is an existing compiled report. The petition is primary data, but it is self-selected. The Ministry statistic, NGO report, industry lifecycle study and viral post are secondary sources because they interpret or report data collected by others.

Source to treat with caution: the industry-funded lifecycle study. Funding does not automatically make it false, but it creates an interest in a favourable conclusion. The team should ask: What alternatives were compared? Were transport and disposal included? Who peer-reviewed it? A lifecycle study can legitimately find that a plastic bottle is 'greener' than a heavy glass bottle under certain assumptions, but that does not settle a campus ban where reusable cups and refill stations are the alternative.

Source to treat with caution: the viral post. It makes a serious health claim with no named authority, study, date or method. It is unverifiable and likely confuses correlation with causation. Using it would damage credibility.

Criteria. Judge all sources by authority, methodology, currency, bias and corroboration. The Ministry statistic is not automatically perfect either: check whether 'campus waste' means weight or volume and which year it covers.

Thesis: The campus should phase in a ban on single-use plastic bottles because the environmental and financial costs outweigh convenience, provided reusable alternatives are subsidised and accessible.

Argument 1: The waste burden is large and costly.

• Evidence: canteen sales data (about 1,100 bottles per week) to show volume.
• Evidence: Ministry of Health statistic (62% of campus waste is plastic) to show share of waste, with a note on definition and year.
• Evidence: NGO report on marine debris to show downstream impact.
• Reasoning: volume plus persistence equals management costs and environmental harm.

Argument 2: A ban is feasible if alternatives are planned.

• Evidence: petition (480 signatures) as a signal of student concern, explicitly labelled self-selected, not as a representative poll.
• Evidence: industry lifecycle study used cautiously to address the counterargument; explain its assumptions and why refillable cups change the comparison.
• Reasoning: feasibility depends on refill stations, subsidy and transition time, not on banning alone.

Counterargument and rebuttal: The industry study suggests plastic may be greener; rebut by narrowing the comparison to single-use bottles versus a campus refill system and by noting the study's funding and scope.

Do not use: the cancer claim. It is unsupported and would undermine the brief.

Conflicting statistics. First check definitions: does '62% of campus waste' refer to weight, volume or item count? Does it include all plastics or only bottles? Second check dates and methods: a Ministry figure may come from a one-week audit or an estimate. Third check scope: campus waste is not the same as national municipal waste. The team should prefer recent, local, methodologically transparent data and present a range rather than false precision. If the canteen data and Ministry figure point in the same direction, the team can say the evidence is consistent even if the exact numbers differ. A footnote should record the discrepancy.

The cancer claim. The team should not lead with it. A viral post is not evidence of causation, and a debating brief that uses it risks losing credibility on stronger arguments. If an opponent raises it, the team can say the claim is not supported by the sources available and that the motion does not depend on it. The brief should stick to waste volume, cost and feasible alternatives.

Principle. Processing information means distinguishing evidence from assertion, reconciling sources where possible, and acknowledging uncertainty where reconciliation fails. Shock value is not a substitute for warrant.