 Ground [Grund] and the Principle of Sufficient Ground [der Satz vom zureichenden Grund] play a significant role in Hegel’s Logic. For Hegel, the demand for ground provides a major source of transition from one thing to another. It is, Hegel says, “the expulsion of itself from itself” (Encyclopedia Logic, §121A). Ground, for Hegel, is the unity of identity and difference: the ground of \(x\) has to explain all features of \(x\), and in sense duplicates it, yet it must also be different from \(x\) in order to have explanatory value and not be a mere petitio principii.