• More than one kind of abstraction
• A handful of interesting philosophy concepts
• Dangers of taking modern logic for granted
• Set theory to topology
• Set theory to the rest of maths
• Short biographies
• Frege (not a bro)
• My bro Kurt Gödel
• Lambda calculus from scratch
• Type-theory
• Categories
• Abstraction in art
• On problem-solving
• What are things made of
• Space objects
• linguistics
• How I do maths

See also some selected notes and tips on learning things.