OK, this may sound really dumb; but can't deflation be solved instantly by just printing more money?
There is a very simple answer to this question: people and banks can choose to save the money printed instead of spending it on goods or investment projects, so prices don't increase anywhere due to significant demand shifts. No need to write 800-900 words about it.
If the secular stagnation hypothesis is true, though, then deflation isn't even the biggest problem anymore. The culprits are the usual ones: aging workforce, labour market adjustment failures, etc. The consequence is that banks don't see any projects as profitable enough (the expected interest rate on these loans outpace inflation, so the real interest rate is negative).
