In this lecture, Professor Rashed demonstrated the influence of Arab mathematics of the 11th and 12th centuries on the ‘new’ mathematics of the European Renaissance. The lecture took place on Friday 25th of June 1999, at Al-Furqan Islamic Heritage Foundation's headquarters, Eagle House in Wimbledon, London, and was part of the Public Lectures series held by the Foundation, in which, prominent thinkers addressed topics that - on the one hand - have their roots in the cultural heritage of Islam, and - on the other - have a bearing on contemporary issues.