A.2 Glossary of Specialized Terms 333 e Hebbian Links: Links recording information about the associative relationship (co- occurrence) between Atoms. These include symmetric and asymmetric HebbianLinks. e Heterarchical Network: A network of linked elements in which the semantic relationships associated with the links are generally symmetrical (e.g. they may be similarity links, or symmetrical associative links). This is one important sort of subnetwork of an intelligent system; see Dual Network. e Hierarchical Network: A network of linked elements in which the semantic relationships associated with the links are generally asymmetrical, and the parent nodes of a node have a more general scope and some measure of control over their children (though there may be important feedback dynamics too). This is one important sort of subnetwork of an intelligent system; see Dual Network. e Higher-Order Inference (HOI): PLN inference involving variables or higher-order func- tions. In contrast to First-Order Inference (FOI). e Hillclimbing: A general term for greedy, local optimization techniques, including some relatively sophisticated ones that involve “mildly nonlocal” jumps. e Human-Level Intelligence: General intelligence that’s "as smart as’ human general in- telligence, even if in some respects quite unlike human intelligence. An informal concept, which generally doesn’t come up much in CogPrime work, but is used frequently by some other AI theorists. e Human-Like Intelligence: General intelligence with properties and capabilities broadly resembling those of humans, but not necessarily precisely imitating human beings. e Hypergraph: A conventional hypergraph is a collection of nodes and links, where each link may span any number of nodes. OpenCog makes use of generalized hypergraphs (the Atomspace is one of these). e Imitation Learning: Learning via copying what some other agent is observed to do. e Implication: Often refers to an ImplicationLink between two Pre