Nick Bostrom's singleton is a world order with a single decision-making power at the highest level — it could be a superintelligence, a world government, or any structure that faces no internal rivals and no external competition. The defining feature is simply: at the top, there is one, and it can prevent any challenge to itself.
The neutral-but-loaded idea
A singleton isn't inherently good or bad. It could end war, coordinate against existential risks, and steer humanity wisely — or it could be a perfect, permanent tyranny with no appeal, no exit, and no second opinion.
Whether a singleton is heaven or hell depends entirely on what sits at the top — and unlike every power in history, there's no balancing force to correct it if it's wrong.
It's the structural skeleton beneath The Benevolent Dictator and AI Sovereign, The Gatekeeper, and The Protector God — each is a kind of singleton, distinguished by how it rules.
Related: The Benevolent Dictator and AI Sovereign · The Gatekeeper · The Value Loading Problem