If money could guarantee someone peace of mind, then the man in person would've spent half of what he's acquired to find peace but what we was going through was beyond his wealth, and he's a prove that one can have all the billions and still not get peace or happiness. I might be wrong though but what's your opinion?
It could be said that this is true because if someone's peace of mind is caused by money, there will be many rich people whose lives are very peaceful.
In fact, there are still many rich people who do not get all of that and in fact they do not find peace at all with the abundant amount of wealth they have.
We will gain peace if we are able to be grateful for anything and we can share it with those closest to us. But even so, wealth will be much better as long as we can enjoy and share with each other, with wealth we can help other people so that they can gain happiness.