Distinction requires both differentiation and boundary. This paper argues that systems lose the capacity to generate and sustain non-trivial distinctions at both extremes of scope. Where a system encompasses vanishingly little structure, there is insufficient differentiation for distinction to arise. Where a system encompasses totality, the boundary required for contrast disappears. These limits differ in construction but are equivalent in effect: both eliminate the conditions under which structured distinction can be generated or maintained. This “horseshoe principle” applies to systems that persist under constraint and explains why capacities such as modelling, representation, and recursive organisation are maximised only within a bounded interval between these extremes.
Joe Alexander Creed (Sat,) studied this question.