Paul Krugman, professor of international trade and economics at Princeton University and Nobel Prize-winning economist, speaks during an event at the 92nd Street Y in New York, U.S., on Tuesday, March 29, 2011. Nobel Prize-winning economist Paul Krugman said last month that Bank of England Governor Mervyn King had 'stepped way over the line' and become a 'cheerleader' for the government's deficit-cutting plans. Photographer: Ramin Talaie/Bloomberg via Getty Images

Though there are many enthusiasts cheering the rise of the virtual currency, bitcoin, experts already declared similar products foolish as early as 1776, according to Paul Krugman.

The Nobel Prize-winning economist wrote in a blog post Friday that famed economist Adam Smith would have “scorned” bitcoins because “mining” them requires expending real resources. Smith criticized the use of gold and silver currency in the 18th century, arguing that valuable resources were being expended to create something that was simply symbolic. Krugman writes that the same can be said of bitcoins.

“Now here we are in a world of high information technology -- and people think it’s smart, nay cutting-edge, to create a sort of virtual currency whose creation requires wasting real resources in a way Adam Smith considered foolish and outmoded in 1776,” he wrote in the Friday post.

Bitcoins are a form of internet currency accepted by some websites to purchase actual goods. The internet money isn't backed by any national government, though. The coins popularity have grown in recent weeks and the total value of outstanding bitcoins surpassed $1 billion earlier this month. Users can buy the coins or “mine” them by running high-level computer programs that take up a lot of memory space and have a slim chance of producing any actual coins.