Girard goes on to say that "equilibrium invariably leads to violence," while justice is really the imbalance that shows the difference between "good" and "evil" or "pure" and "impure." When the past is not differentiable from the present, a violence called sacrificial crises occurs. There will always be differences despite the seeming similarities; otherwise, violence will ensue to "correct" the situation. This experience in poetry is also referred to as a "force, as it were, 'behind' the representative surface of the poetry." The physical is again seen as part of the psychology used by Shakespeare in the language of his sonnets.