to regulate money creation in order to facilitate growth and investment. the mistake wasn't in it's creation, it was in including maintaining unemployment in it's mandate IMO. i found a blog post that puts it into layman's terms fairly well, but I can't find it right now.
basically controlled inflation is far more conducive to economic growth than deflation, which is inevitable under any kind of gold standard in which the money supply is fixed. if banks make loans to people and the money supply is fixed, investment becomes a zero sum game. If one investment pays off, another one elsewhere must not, so venture capital is significantly harder to come by, and a lot of good and likely profitable ideas go unfunded in favor of safer ones. allowing an institution to increase the supply of money as the demand for money rises as new agents enter the economy allows far more than only half of profitable investments to be made and more people (throughout the economy, not "the international banking cartel", whatever the frick that is) better off as a result
edited for clarity and grammar nazism
This post was edited on 12/3 at 8:23 pm