Today his Vanguard index fund is now the largest investment fund in the world, recently overtaking Pimco's main bond fund.
Today though, with stock markets at all-time highs, is index investing the way to go?
Bogle says yes. The low-cost advantage of the index fund provides a long-term advantage that active money managers will in most cases fail to beat.
Over time the index fund wins. Bogle calls it a case of simple mathematics.