Complexity theory · 1971 · Stephen A. Cook
The Complexity of Theorem-Proving Procedures
Connect efficient verification, nondeterministic computation, and polynomial reduction so one complete problem represents a whole class of apparent intractability.
The central move
Connect efficient verification, nondeterministic computation, and polynomial reduction so one complete problem represents a whole class of apparent intractability.
Why it had to exist
Computability separated possible from impossible, but engineers also needed to distinguish feasible procedures from those whose resource growth defeats scale.
Where it leads
Computability limits → resource complexity → reductions → algorithm selection, approximation, and cryptographic assumptions.