Does seeing a green apple prove that all ravens are black?
Claim: "All ravens are black." Logically, this also means: "All non-black things are non-ravens." So a green apple (non-black, non-raven) supports the claim! But how can an apple tell us about ravens? Bizarre!
🤔 Which thinking lens(es) did you use?
Select all the lenses you used:
🌱 A Small Everyday Story
"I saw a green apple!"
"So?"
"It proves all ravens are black!"
"...What? That makes no sense."
"But logically, it does! Just... a tiny bit."
Logic and intuition had a very confusing argument.
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🧠 Thinking habits this builds:
- Understanding logical equivalence
- Distinguishing logical form from practical evidence
- Appreciating proportional reasoning
- Questioning intuitive reactions to valid logic
🌿 Behaviors you may notice (and reinforce):
- Analyzing the strength of evidence
- Recognizing that technically correct can feel absurd
- Thinking about probability and proportion
- Appreciating philosophical puzzles about confirmation
How to reinforce: "You discovered that logic and intuition can clash! The apple technically supports the claim, but the support is so tiny it's practically meaningless. Proportion matters in reasoning!"
🔄 When ideas are still forming:
Children might reject the logical connection entirely. Help them see the equivalence first.
Helpful response: "If something isn't black, can it be a raven? No! So seeing non-black non-ravens confirms what we'd expect. The puzzle is why this feels absurd!"
🔬 If you want to go deeper:
- How many green apples would equal one black raven as evidence?
- Why does the indoor/outdoor context matter for evidence?
- What other logical equivalences seem absurd?
Key concepts (for adults): Hempel's Paradox, confirmation theory, logical equivalence, Bayesian probability, prior probability.