What does it mean to compute? A remarkable claim holds that every intuitive notion of mechanical calculation amounts to the same thing.
A problem solvable in principle may be unsolvable in practice.
Ask whether an arbitrary program will ever stop, and no general method can always answer.
Force a system to squeeze data through a narrow channel and rebuild it, and it must keep only what matters.
A scene is not a heap of features but an arrangement of objects, each with its own properties.
Understanding a few combinations should confer understanding of many.
From a fixed vocabulary we build endless sentences, and from known concepts endless thoughts.
A learner can improve not only at a task but at learning itself.