Financial forecaster Gary Shilling became the latest market analyst to critique cryptocurrencies, remarking yesterday that he views the technology as a "black box" he would not invest in.

The president of Gary Shilling & Co, Inc and a frequent commentator on TV networks, Shilling told Business Insider he takes issue with the lack of clarity behind who invented the concept. Further, he related a recent conversation with a friend during which he asked about the pseudonymous founder, Satoshi Nakamoto, comparing the answer he received with past financial scams.

He told the publication:

But while Shilling is the latest mainstream analyst to chime in on the cryptocurrency, he is certainly not the only one to voice suspicion about the idea. Earlier this summer, JPMorgan Chase CEO Jamie Dimon called bitcoin a "fraud" and predicted its demise at the hand of regulation.

Other observers, however, have taken a more neutral tack.

Recently, BlackRock CEO Larry Fink – head of the world's biggest asset manager – said he was a "big believer" in the idea of cryptocurrencies, though he criticized the spate of speculation in the market.

Gary Shilling image via Youtube/Bloomberg