Theories.si
Big ideas, broken down simply
From string theory to social contract theory to evolutionary psychology - the world's big theories across science, philosophy, and society, explained clearly for the curious mind.
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What you get
Everything Theories.si gives you
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Plain language first
Every big idea explained simply before the technical depth.
layers
Science, philosophy, society
Theories across every field, clearly labeled by type.
scale
Established vs. contested
Know what's proven, what's debated, and what's fringe.
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Saved study threads
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Pricing
Simple plans that grow with you
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Plus
$9/mo
- ✓200 questions per day
- ✓Full saved conversation history
- ✓Extended cross-discipline explanations
Premium
$99/mo
- ✓Unlimited questions
- ✓Deep-dive theory breakdowns
- ✓Everything in Plus