This article presents and discusses the path followed by Hasdai Crescas (1340-1411), medieval Jewish philosopher who lived in Barcelona for the elaboration of his proof for existence of God, formulated from his critique of the evidence presented by Maimonides (1138-1204) in the "Guide of the Perplexed". Crescas's critique starts with the formulation of a general concept of existence applicable to both the necessary being as to the contingent beings. Another interesting aspect of his way to formulate his proof is Crescas's distinction between existence and quiddity in the necessary being, a unique position among the medieval philosophers that introduces an important aspect of immanence in his idea of God, which radically differs from that advocated by Maimonides.
Crescas; Maimonides; existence; quiddity; immanence; transcendence