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the problem currently is, that more and more people cannot take part in the economy, because they dont have access to enough money. The current interest based system increases this year by year. Therefore a currency that is widly distributed can even compete to dollar or bitcoin, because both suffer more and more the distribution problem. Therefore paying with an basic income currency can become much more widly used and easier then paying with BTC, because people simply have access to the currency.

@arcurus I see your point but the problem is that it currently still is too difficult for most people to even use Bitcoin... How should they be able to use 5 different currencies?

true, currently its too difficult to use for normal people.
Technically it can go as easy as credit cards / paypal. Also the internet was difficult to use in the beginning.

In the mid term only two currencies are needed. The local currency like dollar and the global basic income currency. In the long run the basic income currency will dominate all other currencies, still there will be more currencies, but same like dollar only one currency will be mainly used.