今天在看博迪的投资学时,看到下面的句子,有些糊涂

A prospect that has a zeo risk premium is called a fair game .

Risk-averse investors are willing to consider only risk-free or speculative prospects with positive risk premia.

无风险投资项目风险溢酬不也是为0吗?按上面那句话,无风险项目也成了"零和游戏"了.为什么还会有下面这句话.

两句矛盾不?