Using Evidence Effectively in LD Debate
Your arguments are only as strong as the evidence behind them. In Lincoln-Douglas debate, you’re not just throwing out statistics or quoting famous thinkers- you’re building a persuasive, well-supported case. That means using relevant, credible, and properly integrated evidence to strengthen your position. If your opponent calls out weak sources, outdated facts, or misused quotes, your case will fall apart. Here’s how to make sure your evidence works for you, not against you.
Good Sources vs. Bad Sources
Not all evidence is created equal. Judges (and skilled opponents) will spot unreliable or biased sources a mile away.
Use sources that are:
Recent (within five years) – If your evidence is older than this, find something newer. AI and technology change rapidly, and judges won’t take decade-old data on AGI seriously.
From credible institutions – Universities, government agencies, respected research groups (e.g., MIT, Stanford, Pew Research).
Free from obvious bias – A tech company investing billions in AI might not be the best source on AGI safety.
Avoid:
Blogs, opinion pieces, and advocacy websites with no academic backing.
Cherry-picked statistics without full context. If it sounds too convenient, your opponent will challenge it.
Wikipedia as a direct source (but its references can lead you to real evidence).
Facts vs. Quotes: When to Use What
Facts and statistics are for proving something is true. Use them when your argument needs objective support.
- Example (Negative Case on AGI): “According to a 2023 MIT study, AI-driven medical diagnostics reduced errors by 40%, proving AGI’s potential to enhance human well-being.”
Quotes are for establishing a principle or philosophy. Use them when your argument relies on values or ethical reasoning.
- Example (Affirmative Case on AGI): “Kant’s categorical imperative states that we must act only on principles we would universalize. If AGI development risks global harm, it violates this moral standard.”
What not to do:
Don’t throw in a random famous quote just because it sounds good.
Don’t use outdated thinkers on modern topics (Plato had a lot to say about justice, but nothing about artificial intelligence).
Make sure your quote actually supports your argument- not just something vague about morality.
Prepping for Opponent Challenges
If you use evidence, be ready to defend it.
Have citations ready. “According to Stanford’s 2024 AI Ethics report…” sounds far stronger than “I read somewhere that…”
Know what your own source says. If your opponent pulls up the same study and shows you misrepresented it, you’ll lose credibility fast.
Anticipate counter-evidence. If you argue AGI will destroy jobs, your opponent might have a study showing it creates new ones. Have a response ready.
The Bottom Line
Your case is only as solid as the evidence backing it. Use recent, credible sources, integrate facts where they belong, and choose quotes that truly support your argument. If your evidence is strong and well-placed, you’ll not only make your case more persuasive- you’ll make it harder for your opponent to tear it down.