[scriptman]

>Money saved is the very definition of economic inactivity

When people save money, do you really think they put it under a mattress? No, they put it in a financial institution like a bank, who can then use it as capital to loan out further funds. By increasing the amount of saving you should naturally reduce interest rates. Saved money doesn't just drop out of the economy.

Even if someone did put money under their mattress, they are risking having inflation eat away as its value. Also, if they never spend their money, all they have done is increase the value of everyone else's money. Prices have to fall to the point that markets will clear.