The philosophical principle that everything that happens has an infinite number of reasons, none of which is ever sufficient to fully explain why it happened. This challenges Leibniz's principle of sufficient reason, which claimed that everything has a reason. The principle of insufficient reason acknowledges that explanation is infinite regression—you can always ask "why" again, and there's always another layer, another cause, another factor. Your car didn't break down just because the alternator failed; it failed because of manufacturing tolerances, material fatigue, your driving habits, the phase of the moon, and the cosmic background radiation. The reasons are infinite; the explanation is always incomplete. This principle is comforting because it means nothing is ever your fault alone, and terrifying because it means nothing can ever be fully understood.
Example: "He asked why his relationship ended, seeking one sufficient reason. His therapist invoked the principle of insufficient reason: 'There are infinite reasons—communication patterns, childhood wounds, mismatched expectations, the alignment of planets if you're into that. No single reason will ever be enough. The search for one is the problem.' He left with infinite reasons and no closure, which was exactly the point."
by Dumu The Void February 15, 2026
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