This book contains the edited versions of papers presented at the Fourth Irish Conference on Artificial Intelligence and Cognitive Science (AICS'91), which was held at University College, Cork, Ireland on 19-20 September 1991. The main aims of this annual conference series are to promote AI research in Ireland, to provide a forum for the exchange of ideas amongst different disciplines concerned with the study of cognition, and to provide an opportunity for industry to see what research is being carried out in Ireland and how it might benefit from the results of this research. While most of the participants at the conference came from universities and companies within Ireland, a positive feature was the interest shown from outside the country, resulting in participants from Britain, USA and Italy. The keynote speaker was Professor James A. Bowen, North Carolina State University, who spoke on future trends in knowledge representation. The topics covered in the presented papers included fundamental approaches to AI, natural language, knowledge representation, information retrieval, deduction, epistemics and vision. The sponsors of the conference were Digital Equipment Co. (Galway) and Eolas, the Irish Science and Technology Board. March 1992 Humphrey Sorensen Contents Section 1: Foundations and Methodologies Toward a New Foundation for Cognitive Science S. 6 Nuallain. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Towards an Adequate Cognitive Model of Analogical Mapping M. T. Keane and S. Duff. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 HOST: A HOlistic System Theory G. Hartnett and H. Sorensen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .