Time and proportion.
The Greeks had two words for time. Chronos is the time that passes: measured, counted, the same for everyone. Kairos is the time that opens: the right moment, which comes once and does not wait.
καιρὸν γνῶθι, know the right moment, is attributed to Pittacus of Mytilene, one of the Seven Sages.
φ is the golden ratio, 1.618. Its inverse, 0.618, divides a whole so that the smaller part relates to the larger as the larger relates to the whole. It appears in the spirals of sunflower seeds and in the arrangement of leaves. Traders use it to mark where a move may pause.
Kairo is where the two meet. φ answers where. Kairos answers when. A level without timing is a wish. Timing without a level is a guess.
Chronos counts. Kairos decides.