Just yesterday I had a conversation with a person who studied economy and finances at a University. He said that any Economic system to work propoerly needs some inflation. Since Bitcoin is a deflationary currency by design he said there's no way Bitcoin would replace all the money in the world.
It depends on your definition of economy and what is meant by inflation. Bitcoin doesn't have inflation but it has "level of difficulty" in mining. So, in a sense, it has the same type of "deterrent," or intangible force acting against the wide proliferation of the monetary unit. It's like friction in Physics. It opposes all motion and is responsible for things wearing out, so people tend to think of it as a bad thing. But then there's ice on the road, and over-reduction of friction becomes much worse.
By fine tuning the counter-force, in the real world and in the economics of bitcoin, you get the desired result of rewarding those who were the early participants.