Kabir, the 15the century Indian mystic poet, wrote:
जिन खोजा तिन पाइयाँ गहरे पानी पैठ
मैं बौरी डूबन डरी रही किनारे बैठ
Those who were searching found by diving deep into the waters
I foolishly feared drowning and remained on the shore.
It’s not possible to know what is lost until it is already found. Not even knowledge, on the shore is just a vague sense of loss.