To understand what they meant, Cyc would have to grasp such concepts as time, space, geopolitics, history, mortality and the complexities of human motivation. Cyc flunked the test first time out, but its failures acted as a guide. When it ran into something that its knowledge couldn't account for, it asked questions. Lenat answered them. Cyc's mind is like an exhaustively cross-referenced encyclopedia.
Every thrush is a bird.
Every hummingbird is a bird. Every raven is a bird. Every ibis is a bird. Further on, the rules become increasingly precise. X evokes positive sympathy.