The stupefying success of Artificial Intelligence (AI) for specific problems, from recommender systems to self-driving cars, has not yet been matched with a similar progress in general AI systems, coping with a variety of (different) problems. This dissertation deals with the long-standing problem of creating more general AI systems, through the analysis of their development and the evaluation of their cognitive abilities. It presents a declarative general-purpose learning system and a developmental and lifelong approach for knowledge acquisition, consolidation and forgetting. It also analyses the use of the use of more ability-oriented evaluation techniques for AI evaluation and provides further insight for the understanding of the concepts of development and incremental learning in AI systems.Keywords: artificial intelligence, general-purpose learning systems, inductive programming, reinforcement learning, forgetting, task difficulty, cognitive development, evaluation of artificial systems, intelligence tests
Extended AbstractIn the light of all the astonishing achievements in recently AI research, it is becoming increasingly clear that creating artificial intelligence is much more than "pattern matching". However, although it would be unfair to deny that some current AI systems exhibit some intelligent behaviour (especially those that incorporate some learning potential), in general terms, most AI research is focused on designing AI systems for a particular functionality or adapted for a specific problem with no intention whatsoever of featuring intelligence. Up to date, the vast majority of the computer models are mindless rule-followers or cleverly written computer program doing statistical calculations and making predictions based on them. However, what it would mean for a computer to behave in an intelligent way? This thesis [9] states that the answer lies in the construction of systems that go beyond task specific scenarios into more general-purpose ones thus able to learn automatically, not pre-programmed or without fixed handcrafted features.Given the above challenge, in the presented dissertation we characterise a series of human intelligence attributes (incremental, developmental and lifelong learning) and cognitive-oriented procedures (memory and forgetting) that, combined with the use of symbolic AI and symbolic learning, have helped us to develop both a general-purpose learning approach as well as a knowledge handling tool. This ambitious issue should, furthermore, pervade the evaluation procedures in AI where systems are usually evaluated in terms of task performance, not really in terms of intelligence. Hence, AI evaluation must necessarily be linked to the purpose of the discipline: general AI systems should require an ability-oriented evaluation in the same way that specialised AI systems should require a task-oriented evaluation.Particularly, and regarding the construction of more general AI approaches, this thesis contributes with a pair of settings for learning and knowledge acquis...