Excellent point. In other words, if you can earn a 5% (real) risk-free return by stuffing $100 bills under your mattress, you're much less likely to make a risk

Excellent point. In other words, if you can earn a 5% (real) risk-free return by stuffing $100 bills under your mattress, you're much less likely to make a risky investment expected to make a 6% (real) return, and definitely won't make any investments earning 4%.