Irving Fisher,
The Purchasing Power of Money…
“ The theory of bimetallism contemplates the circulation side by side of two metals; that of polymetallism looks to the contemporaneous circulation of more than two. So long as several metals could be maintained in circulation together, the price level might fluctuate less than if one metal only were used. But all of the theoretical objections against bimetallism apply also against polymetallism. One metal would eventually drive all the others out of a country, or,—if polymetallism were international,—into the arts. ”
