While it somewhat lacked in structure, a good time was had by everyone in the live chat section of the big Warren Mosler vs Bob Murphy debate last night. You can see a replay of the debate here . One of Mosler's running themes (and which Murphy turned into a running gag) was the idea that he (Mosler) could give his business card a positive price by requiring members of the audience to hand over said card to Mosler's bouncer should they wish to leave the room unmolested. Voilà , modern fiat money. In order to get his fiat cards out into the audience, presumably Mosler would have had to spend them into existence by purchasing stuff from the the audience. Only then would audience members be able to afford to leave the room without being subjected to the bouncer's whims. In the MMT literature, this is called twintopt .* A state imposes an obligation on its citizenry to pay a tax, and then dictates what good or item (the "twintopt") will be sufficient to discharge that ...