Every psychophysical organism is an instrument of present (cosmic self-) consciousness.
Any organism needs some memories to function in the present.
However, many memories are distractions from present awareness.
The first person singular pronoun is essential to memory.
The thought, "I remember...," affirms both the present existence and the temporal endurance of the subject.
"I" means either this organism with its particular history or a present subject transcending history.
Thus, "I should have acted differently then" or "I see that now."
Subjects with different histories meet in the present.