[…] if the distinctions of ±anterior, ±irrealis, and ±nonpunctual are the TMA distinctions consistently made in creole languages, and if these distinctions struggle to emerge, as they seem to, in the course of natural language acquisition, then they represent the primary TMA distinctions made in the earliest human language(s), and appear in all three places because of their naturalness.
- Bickerton (1981), Pag. 280

Alone of the three TMA distinctions, punctual-nonpunctual correlated with observable phenomena. The realis-irrealis distinction contrasts observed events with events that are unobservable, at least at the time of speech; the anterior-nonanterior contrasts not events at all, but the relative timing of events, a highly abstract feature.
- Bickerton (1981), Pag. 284

[…] we can claim that according to four sets of criteria–age of infrastructure, age of functional utility, time of child acquisitions, and sequence within Aux –the three basic TMA distinctions are ranked in the order: nonpunctual first, irrealis second, and anterior third.
- Bickerton (1981), Pag. 286