Magellan chairman Hamish Douglass and Platinum boss Andrew Clifford agree negative interest rates have crippled European banks, but the biggest risk to the equity market is that a negative rates mentality is so embedded that investors think there's no way back.

"This belief about zero interest rates is I think a very, very strong consensus amongst investors the world over," Mr Clifford, the chief executive and chief investment officer of Platinum Asset Management told Morningstar's conference in Sydney on Thursday.