 There are also reasons to consider weaker fuzzy logics. For example, it can be argued that the assumptions forcing the interpretation of the conjunction &amp; to be a t-norm are too strong. In particular, the assumption that \(1\) is its neutral element enforces a definition of tautology as a formula always evaluated to \(1\) and the consequence relation as preservation of the value \(1\) – that is, \(1\) is the only designated value in the  semantics.[3]  A natural way to introduce logics with more than one designated truth-degree is to assume that the neutral element for the interpretation of &amp; is a number \(t &lt;1\). It can be shown that in this situation the designated truth-degrees are exactly those greater than or equal to \(t\). Such interpretations of conjunctions are called uninorms. The logic of left-continuous uninorms was axiomatized in Metcalfe &amp; Montagna (2007).