An introduction to Logic for Computer Science Sujata Ghosh ISI Chennai [email protected] What is logic? What is logic? Reasoning is typically a human activity. What is logic? Reasoning is typically a human activity. There are inference rules which determine whether an argument is correct or not. What is logic? Reasoning is typically a human activity. There are inference rules which determine whether an argument is correct or not. Logic is the study of reasoning, in particular, the study of these inference rules. Example argumentAn example in physics in Physics An example in Linguistics Intelligence without representation* Rodney A. Brooks MIT Artificial Intelligence Laboratory, 545 Technology Square, Rm. 836, Cambridge, MA 02139, USA Received September 1987 Brooks, R.A., Intelligence without representation, Artificial Intelligence 47 (1991), 139–159. * This report describes research done at the Artificial Intelligence Laboratory of the Massachusetts Institute of Technology. Support for the research is provided in part by an IBM Faculty 9 Development Award, in part by a grant from the Systems Development Foundation, in part by the University Research Initiative under Office of Naval Research contract N00014-86-K-0685 and in part by the Advanced Research Projects Agency under Office of Naval Research contract N00014-85-K-0124. Abstract Artificial intelligence research has foundered on the issue of representation. When intelligence is approached in an incremental manner, with strict reliance on interfacing to the real world through perception and action, reliance on representation disappears. In this paper we outline our approach to incrementally building complete intelligent Creatures. The fundamental decomposition of the intelligent system is not into independent information processing units which must interface with each other via representations. Instead, the intelligent system is decomposed into independent and parallel activity producers which all interface directly to the world through perception and action, rather than interface to each other particularly much. The notions of central and peripheral systems evaporateeverything is both central and peripheral. Based on these principles we have built a very successful series of mobile robots which operate without supervision as Creatures in standard office environments. 1. Introduction • We must incrementally build up the capabilities of Artificial intelligence started as a field whose goal intelligent systems, having complete systems at was to replicate human level intelligence in a each step of the way and thus automatically ensure Intelligencemachine. without representation*that the pieces and their interfaces are valid. Early hopes diminished as the magnitude and • At each step we should build complete intelligent Rodneydifficulty A. Brooks of that goal was appreciated. Slow progress systems that we let loose in the real world with real was made over the next 25 years in demonstrating sensing and real action. Anything less provides a MIT Artificial Intelligence Laboratory, 545 Technology Square, Rm. 836, Cambridge, MA 02139, USA isolated aspects of intelligence. Recent work has candidate with which we can delude ourselves. Received tendedSeptember to concentrate1987 on commercializable aspects of Brooks, R.A.,"intelligent IntelligenceAn assistants" without example representation, for human workers.Artificial Intelligence 47in (1991), 139–159.WeArtificial have been following this approach and have built a series of autonomous mobile robots. We have * This reportNo describes one talks research about done replicating at the Artificial the Intelligence full gamut Laboratory of of thereached Massachusetts an unexpected Institute of Technology.conclusion Support(C) and for thehave a research ishuman provided intelligence in part by an any IBM more. FacultyIntelligence Instead 9 Development we see Award,a retreat in part by a grantrather from radical the Systems hypothesis Development (H). Foundation, in part by the University Research Initiative under Office of Naval Research contract N00014-86-K-0685 and in part by the Advanced Research Projects Agencyinto specialized under Office ofsubproblems, Naval Research suchcontract as N00014-85-K-0124. ways to Intelligencerepresent knowledge, without natural languagerepresentation* understanding, (C) When we examine very simple level intelligence Abstract vision or even more specialized areas such as truth we find that explicit representations and models maintenance systems or plan verification. All the of the world simply get in the way. It turns out ArtificialRodney intelligence A. Brooks research has foundered on the issue of representation. When intelligence is approached in an incremental manner, with strict reliancework on in interfacing these subareasto the real isworld benchmarked through perception against and theaction, reliance on representationto be better todisappears. use the worldIn this aspaper its ownwe outline model. our approachMITsorts Artificial to incrementallyofIntelligence tasks Laboratory, humans building 545 Technologycompletedo within Square, intelligent Rm.those 836, Creatures. Cambridge, areas. MAThe 02139, fundamental USA decomposition of the intelligent system is not into independent information processing units which must interface with each other via representations. 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