Abductive Reasoning : Backward and Forward

We propose to reconsider abductive reasonning in the context of empirical reasonning, and to investigate its deep relations with constraint-based reasonning, a currently very successfull approach used in the problemsolving community. 1 The Roots of Abduction Abduction has been proposed in the first years of this century by the logician and philosopher C. S. Peirce as a new inference mechanism for logical system along induction and deduction [ 16 ] . To quote Peirce himself (Collected Papers, 6.524) : " The first starting of a hypothesis and the entertaining of it, whether as a simple interrogation or with any degree of confidence, is an inferential step which I propose to call abduction (or retroduction)." The alternative denomination of "retroduction", that have been first used by Peirce in 1898 and abandonned circa 1901, shows well the fact that the key issue in abduction is to go back from the facts to the hypotheses. But abduction is more than that and it differs form induction b..