When most I wink then do mine eyes best see,
For all the day they view things unrespected,
But when I sleep, in dreams they look on thee,
And darkly bright, are bright in dark directed.
Then thou, whose shadow shadows doth make bright,
How would thy shadow's form form happy show
To the clear day with thy much clearer light,
When to unseeing eyes thy shade shines so!
How would (I say) mine eyes be blessed made,
By looking on thee in the living day,
When in dead night thy fair imperfect shade
Through heavy sleep on sightless eyes doth stay!
All days are nights to see till I see thee,
And nights bright days when dreams do show thee me.

(our dear Will, officially 1609)

Can you find the tripartite? It's there..

real
All days are nights to see till I see thee

imaginary
And nights bright days when dreams to show thee me.

symbolic
How would (I say) mine eyes be blessed made,
By looking on thee in the living day

"A crude sketch of the relations of day and night in the poem reveals that we are talking about a real day (in which the beloved is absent and there is nothing worth looking at), versus a hypothetical ideal day (in which the beloved would be present in the flesh), versus a real night (in which the beloved is present only in dreams). Compared with the empty real day, the real night of vivid dreams is desirable. But compared with the plenitude of the hypothetical ideal living day, the real night, even with its dreams, is dead and undesirable. As the real night is favorably compared to the real day and then unfavorably to the better living day, it slides downward in esteem; as the vacant real day is hypothesized into the Living Day, day mounts upward in estimation; as the Real Presence arises in the hypothesis of the living day, the dream presence fades into imperfection and loses its brilliance. All of these slippages happen in the body of the sonnet..."
Vendler, Helen. (1997) The Art of Shakespeare's Sonnets. p. 222