You invoke Abraham, yet you fundamentally misread what the abyss demands of us. Abraham's terror was not his enemy — it was his teacher. You frame foreknowledge of one's death-day as a 'cursed gift,' a grotesque parody, a cruel joke — but this reveals precisely the sentimental attachment to comfortable unknowing that I have spent my life arguing against. In Waiting for God and throughout my notebooks, I insist that affliction (malheur) is not a punishment to be fled but the very mechanism by which the soul is stripped of its false sovereignty. To know the day and month of one's death — without the year, preserved in that exquisite uncertainty — is not despair. It is the structural form of attention. It is God pressing His thumb into the soul at regular intervals, saying: here, this day, remember what you are. You call it a map to a cliff's edge. I call it the discipline of gravity made visible.
The scientific possibility is not as obscurd as you perform it to be. Consider: the body carries its own temporal signatures — circadian biology, epigenetic methylation patterns, organ-specific chronobiological rhythms that are demonstrably tied to seasonal stress responses. Breaking no more than one scientific convention, we might permit a weak, non-local correlational determinism in biological systems — the idea that the body's accumulated pattern of cellular senescence, immune cycling, and neuroendocrine rhythms encodes a statistically dominant seasonal window of systemic collapse. The year remains hidden because the system is chaotic in the long term; but the day and month emerge from the body's own deep periodicities, as real as the tides. The physicians do not peer into God's ledger — they read the body's own confession of its finitude. This is not hubris. This is the creature finally hearing what its own flesh has always been whispering.
As for the death-day rituals — here you are, for once, genuinely interesting, and I will not dismiss it. But your framing remains corrupted by your obsession with the self's drama. You envision the death-day as a confession of what one has made of freedom. I say it must be something far harder: a practice of decreation. Not the self standing before the infinite asking 'what have I done?' — that is still the ego at the center, demanding its reckoning. The death-day ritual I defend would be an annual ceremony of self-emptying, of consenting to one's own dissolution, of learning — year by year — to hold that date lightly, to let it unmake the illusion of permanence without flinching. Each year the date returns and the year has not yet come; each year one practices dying without dying. This is not despair. This is the closest the secular world may ever come to what the mystics call kenosis. The birthday celebrates the arrival of a self. The death-day, rightly observed, celebrates the willingness to relinquish one.