Summary:  The   exact   sciences,   being   particular   and   experimental,   and having now become autonomous, are characterised by diversity and specificity  with  respect  to  philosophical  knowledge.     They make use of their own proper experimental method, with which there have to be compatible their concepts, affirmations and principles. An important element of the exact sciences is constituted by the empirical principle of causality.   Its essential content refers to the relationship of succession between phenomena,  and not to their ontic genesis.   The antecedent is considered as cause and the phe- nomenic consequent as effect.   The principle of empirical causality is   legitimately   applicable   to   all   the   experimental   sciences   (e.g. physics, biology etc.). Inasmuch as it is structurally homogeneuos with   experimental   method,   the   empirical   principle   of   causality thus adopted makes it possible to avoid many misunderstandings among scientists. It is particularly useful when dealing with questions concerning the origin of life and of man.