Simplexity and the reinvention of equifinality

Some earth surface systems apparently exhibit deterministic chaos, where small differences in initial conditions produce increasingly divergent results. This casts doubt on the venerable concept of equifinality, whereby surface features converge to similar forms. However chaotic systems exhibit a broader-scale order, and their complex patterns occur within well-defined limits. This broad-scale order arising from smaller-scale chaos produces simplexity, where simple rules and regularities emerge from underlying complexity, when the broad-scale structures are independent of the fine-scale details. Chaos precludes equifinality, sensu stricto, at certain scales, but simplexity produces equifinality at others. Simplexity is illustrated in a case study of soil-landform relationships.