Philosophy
The Epistemology of Skill and Knowing-How Versus Knowing-That
Quick fact
Philosopher Gilbert Ryle argued that knowing-how cannot be reduced to knowing-that, because if every skill required knowing a fact, we'd face an infinite regress of knowing facts about how to apply other facts.
Why this is interesting
You can read every manual on riding a bicycle, yet still fall over the moment you sit on the seat. What does the bike-rider know that the manual-reader doesn't?