Great Thought Experiments
Like Duolingo, but for Great Thought Experiments. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.
For the part of you with thirty open tabs that never became anything.
Free during early access · No credit card · iPhone & Android

Key ideas in Great Thought Experiments
- Numerical identity
- Qualitative identity
- Spatio-temporal continuity
- Material origin
- Mereological essentialism relates identity to specific parts
- The distinction between numerical and qualitative identity
- Functionalism focuses on the role an object plays
- Aristotelian 'form' refers to the structure or design
- The conflict between spatio-temporal continuity and original components
- Matter refers to the physical substance
- Mapping philosophical theories of identity to their definitions
- The philosophical preference for form over matter in identity
- The problem applies to any entity undergoing gradual part replacement
- Biological organisms and evolving organizations share this identity paradox
- The 'person' follows the consciousness and memory
- The physical body is merely the 'man' or biological vessel
You've tried the other tabs
Thirty open tabs. Four facts you actually kept.
You watched. You nodded. By Sunday it was gone.
One answer, then back to scrolling.
Eight weeks. You meant to finish. You didn't.
Tomo gives Great Thought Experiments the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.
Here's what playing it feels like
A real question from this course. Take your best guess.
If we ask whether a ship remains the 'same' after a repair, which type of identity are we investigating?
Get it right to open this lesson and 53 more in the app.
Where Great Thought Experiments takes you
Explore the boundaries of logic, ethics, and reality through history's most famous mental simulations. Challenge your intuition and learn how philosophers and scientists use 'Gedankenexperiments' to solve the unsolvable.
- 1
Identity and the Self
- The Ship of Theseus
- Locke’s Prince and the Cobbler
- Parfit’s Teletransporter Paradox
- The Brain in a Vat
- 2
Ethics and Moral Dilemmas
- The Classic Trolley Problem
- Foot’s Transplant Scenario
- The Survival Lottery
- Rawls’ Veil of Ignorance
- The Experience Machine
- Thomson’s Violinist
- 3
The Nature of Mind and Knowledge
- Mary’s Room (The Knowledge Argument)
- Searle’s Chinese Room
- The Philosophical Zombie
- 4
Physics and the Fabric of Reality
- Maxwell’s Demon
- Schrödinger’s Cat
- Einstein’s Chasing a Light Beam
- The Twin Paradox
- Laplace’s Demon
4 sections · 18 units · 54 levels. Built to play, not to enroll.
You pick the voice
Great Thought Experiments is taught in the The Professor style: clear, structured, thorough. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.
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Start Great Thought Experiments today.
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