“Soft concepts” for Soft Computing in “soft sciences” on 20 years of “Soft Computing”

20 years after the appearance of Soft Computing, this paper serves reflecting cognitions on “soft concepts”, Soft Computing and “soft sciences”. We consider soft concepts and hard concepts that have to be distinguished from each other. “Hard” concepts have been strictly defined in logics more than 100 years ago, but “soft” concepts have not been used in science before the 21^st century. We give a brief view on the history of Soft Computing, we distinguish “hard” and “soft” concepts in science, and we consider the opposite pair “Hard Computing” and “Soft Computing”. We separate hard sciences and soft sciences and we give some examples for the key role that soft concepts and Soft computing could play in future soft sciences.