Switching from Proof of Work (PoW) to Proof of Stake (PoS) does not break the blockchain solution to the Byzantine Generals Problem. It simply replaces the underlying economic cost function while preserving the essential conditions required for Byzantine-fault-tolerant consensus. At its core, the Byzantine Generals Problem in public blockchains demands one thing: that honest nodes converge on a single canonical history even when some participants behave maliciously. Nakamoto-style consensus achieves this probabilistically as long as two assumptions hold: Honest participants control the majority of the scarce resource that governs block production, and Rewriting history is economically prohibitive. PoW and PoS differ only in what that scarce resource is. In PoW, the resource is hashing power—energy + specialized hardware. An attacker needs >50% of global hashpower. In PoS, the resource is staked tokens—economic value explicitly placed at risk. An attacker needs >50% (or >⅔ in BFT-style chains) of all staked coins, and risks those coins being slashed. In both cases, the system remains secure as long as honest participants control the majority of the relevant resource. How PoS Preserves Safety and Liveness Modern PoS protocols retain the two core Byzantine properties: Safety – Honest nodes do not finalize contradictory histories. This is enforced through: Ethereum’s Casper/Gasper (finality once ≥⅔ of stake attests), Tendermint/BFT-style consensus (instant finality with ≥⅔ honest participation), or probabilistic-finality PoS designs (longest-chain variants)....