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Actually it is production that creates wealth and production is stimulated by consumption.
and consumption is made possible by production.
When world currency would be deflationary then consumption will slow because everyone will be motivated to hold onto their money,
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... which means that in the current inflationary environment, nobody would ever sell anything, because they would get more money tomorrow.
This is nonsense, every trade has two parties, that include you selling your work-hours.
Inflationary means the seller will quickly turn his new money into something of real value. Deflationary means that the buyer will quickly sell more to recoup his money. None of these forces have more weight than the other.
The difference is that in an environment with inflation, it is more rational to hold no or a negative amount of money when you want to save. With deflation, it is more rational to hold money, and value will be souped up in the money system in stead of real assets.
Inflation is wasteful because of all the unnecessary resources you take up when you save, and it takes power away from you because you are in constant debt. Deflation economises real resources and allows you to use your saved resources more freely.
Even more important, the value lost from the money in inflation ends up somewhere, but not in your pockets.
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