 The hybrid of two fully determined connectives may even be completely undetermined (satisfy no determinant-induced conditions at all, that is). This will be the case, for example, if we hybridize not conjunction and disjunction, but conjunction and negated conjunction (sometimes called nand). By using negation in this way, we prevent any overlap in the determinant-induced conditions which are satisfied by the hybrid, though there still remain some non-trivial properties (commutativity, for example) as well as extensionality—the point of this mention of hybrids—since any hybrid of fully determined connectives will still be extensional (according to the intersection, that is). Of course, one can also hybridize connectives which are not themselves fully, or even partially determined—for example, one could investigate the common properties of ☐ and ♢ according to the smallest normal modal logic (commonly called K), though this example would for its most natural development require us to go beyond the simple account of hybrids given here, since it would have to attend to the simultaneous presence of the Boolean connectives alongside these modal operators. A better known modal example of hybrids is that of the ☐ operator in Łukasiewicz’s Ł-modal logic (not that Łukasiewicz used this notation for his necessity operator), which is a hybrid of 1-ary connectives for the 1-place identity and constant-false truth-functions. (See Chapter 1 of Prior (1957) on this point; further references may be found in Section  5.)