Importantly, with protolanguage, a semogenic threshold has been crossed: from ‘senser-doing’ (‘behaver-behaving’) to ‘sayer-saying’. With ‘sayer-saying’, as Halliday & Matthiessen (1999: 514, 584) point out, the contents of consciousness are not only externalised, but transformed into events of a different kind: those that do not require a conscious source.
Or perhaps, with protolanguage, we should say ‘proto-saying’, since although it involves the externalising projection of the contents of consciousness (so ‘saying’), it involves the projection of meanings (‘ideas’) rather than wordings (‘locutions’), since it is only with emergence language that the contents of consciousness becomes stratified into meaning and wording.