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Cereal, soup, and the boundaries of a definition

Cereal sits in liquid and is eaten with a spoon, but is that enough to make it soup? A definition can admit surprising cases or exclude familiar soups. A kitchen category need not behave like a mathematical rule with a perfectly sharp boundary.

3–5 min

Questions you could explore

  • Can you make a rule that includes ordinary soups without admitting everything you hoped to exclude?
  • Would a category based on common examples handle borderline foods differently from a strict checklist?

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Ethics and philosophy

Deduction and induction make different kinds of claim

Deduction asks what must follow from stated premises, while induction uses observations to suggest what may happen next. A valid deduction still needs true premises for a true conclusion; further observations can overturn an inductive generalization.

3–5 min

Deduction and induction make different kinds of claim

Ethics and philosophy3–5 minDeduction asks what must follow from stated premises, while induction uses observations to suggest what may happen next. A valid deduction still needs true premises for a true conclusion; further observations can overturn an inductive generalization.

Ethics and philosophy

Why does the trolley problem change when you change how someone is saved?

A runaway trolley threatens five people. Redirecting it onto a track with one person and pushing someone into its path can produce different moral reactions, even when the numbers match. Explore how intention, duties, and using a person as a means influence the judgment.

3–7 min

Why does the trolley problem change when you change how someone is saved?

Ethics and philosophy3–7 minA runaway trolley threatens five people. Redirecting it onto a track with one person and pushing someone into its path can produce different moral reactions, even when the numbers match. Explore how intention, duties, and using a person as a means influence the judgment.

Ethics and philosophy

Is the red you see the same red that I see?

We can agree that a tomato is red and choose the same matching paint. Does that agreement show that red feels the same to each of us? The puzzle separates what we can compare publicly from what another person’s experience is like.

4–6 min

Is the red you see the same red that I see?

Ethics and philosophy4–6 minWe can agree that a tomato is red and choose the same matching paint. Does that agreement show that red feels the same to each of us? The puzzle separates what we can compare publicly from what another person’s experience is like.

Cereal, soup, and the boundaries of a definition | Speech Topic | speaking.app