Abstract

A scientific and political policy of innovation, according to Leibniz, has to start with the programmatic distincton between knowledge already available and knowledge still to be discovered . Gradually both, synthetic and analytic methods, can serve invention. If deduction is used. e. g. by combining tones to all possible musical themes, a further selection is nevertheless necessary. Human genius, gifted with imagination, can be compared with a sieve . Selection becomes the mark of contingency within the network of rationality. In Leibniz's lifelong program of the "ars combinatoria", ars inveniendi has a double task: to develop a purely rational structure and to realize this structure in a more contingent and pragmatic context. Various instruments are discussed: memory, schemata, models, historical examples. Ars inveniendi expresses so the fundamental ontological tension in Leibniz's philosophy