 System CK axiomatizes the truth-conditions laid out in (VSC)-rm. CK has been called the basic conditional logic by Chellas (1980), as it is meant to be the counterpart to the basic system K of modal logic. In particular it yields the same theorems as system K relative to a fixed modality \(\Box_{A}\). Thus, it satisfies conditional analogues of the axiom K of standard modal logic (viz., the axiom CK: \((A&gt;B) \supset((A &gt; (B\supset C)) \supset(A &gt; C))\)) and of the rule of Necessitation (viz., the rule CNec: from \(C\) infer \(A&gt;C\)). It can be described as the smallest logic closed under LLE and RCK (the latter entailing LT, RW and AND), and is also called a normal conditional logic because of that. The logic Ck corresponds to its hyperintensional variant, in which LLE is dropped.