A basic difference between a pay-as-you-go (PAYGO) public pension system and one with fully funded private accounts lies in the startup. From its inception, a PAYGO system can pass contributions from current workers to current retirees. A funded system must either spend decades accumulating tax revenues before beginning benefit payments, or society must provide external funds to create the system's initial account balances. This paper shows that the same logic governs reform of a PAYGO into a private account system. Presuming that only the second procedure above is feasible for reform, one would have to find external funds to create initial account balances. After that step, the new system could be autonomously viable