@InProceedings{Horcik:CTU03, IS = { zkontrolovano 23 Apr 2003 }, UPDATE = { 2003-02-27 }, author = { Hor{\v c}{\'\i }k, Rostislav }, title = { Mathematical Properties of Fuzzy Logics }, booktitle = { Proceedings of Workshop 2003 }, book_pages = { 1212 }, publisher = { CTU Publishing House }, address = { Prague, Czech Republic }, isbn = { 80-01-02708-2 }, year = { 2003 }, month = { February }, day = { 10-12 }, venue = { Prague, Czech Republic}, organization = { Czech Technical University in Prague }, pages = { 28--29 }, project = { MSM 212300013, GACR 201/02/1540, CTU 0208613, CEEPUS SK-042 }, autorship = { 100 }, psurl = {}, keywords = { fuzzy logic, many-valued logic, validation sets }, annote = { In this paper we generalize the notions of tautology and contradiction to the case of fuzzy logic. This leads to the notion of validation set. The validation set of a formula is the set of all truth values which the formula may achieve. }, }