Via Marginal Revolution, I see that Edward Hugh says
So, what do you do about the problem of secular stagnation, if that is what it is? Again here there is divergence of opinion. Some still seek to treat the phenomenon as if it were a variant of the liquidity trap issue. Most notably Paul Krugman, who continues to hope that massive quantitative easing backed by strong fiscal stimulus will push economies like the Finnish one back onto a healthy path. But if the issue is secular stagnation, and the root is population ageing and shrinking, it is hard to see how this can be.
Very good. People have to realize that sometimes negative growth and dissaving is optimal. Just think of any elderly man. His productivity used to be much higher, before he retired or cut back his hours of work, so he has negative personal product growth. His savings used to be higher too, before he started drawing on his retirement account. Does he have an economic problem and needs to be forced to go back to work? No. Multiply him by 10 million and nothing changes.