External Vs Internal Temporal Conjunction

1. External Temporal Conjunction

Halliday & Hasan (1976: 239, 240):

… it is a relation between events […] first one thing happens then another.  The time sequence […] is […] in the content of what is being said. 

… the cohesion has to be interpreted in terms of the experiential function of language; it is a relation between meanings in the sense of representations of ‘contents’, (our experience of) external reality. 

… those which exist as relations between external phenomena …

2. Internal Temporal Conjunction

Halliday & Hasan (1976: 239, 240):

The time sequence is in the speaker’s organisation of his discourse. … a relationship between different stages in the unfolding of the speaker’s communication role — the meanings he allots to himself as a participant in the total situation. 

… the cohesion has to be interpreted in terms of the interpersonal function of language; it is a relation between meanings in the sense of representations of the speaker’s own ‘stamp’ on the situation — his choice of speech role and rhetorical channel, his attitudes, his judgements and the like. 

… those which are as it were internal to the communication situation.