What type of money is accepted by cultures around the world and keeps it value even the government collapses? Since Old Testament times, the answer is gold. And the precious metal is unlikely to lose favor with goldbugs anytime soon.

Cameron and Tyler Winklevoss, however, argue that the virtual currency Bitcoin can serve as a substitute to gold. Speaking on Wednesday at a BusinessInsider event in New York, the twins argued that Bitcoin is not only a permanent new feature of the financial landscape, but added that a single Bitcoin will one day be worth $40,000 (one unit is now worth a record $400 apiece).

The Winklevosses, famous for their role in the early days of Facebook, are hardly neutral, of course. They own buckets of Bitcoin –around $40 million worth at current prices — and are planning to launch a way for people to buy it via the stock market