(CNBC) — Look to the stock market and you’d assume Wall Street was doing just fine. The S&P 500 has come back to March highs, the Dow is back to positive for 2018, and the Nasdaq is at fresh records.

It’s all built on shaky foundations, said longtime market bear and former Republican Congressman Ron Paul.

This market is in the “biggest bubble in the history of mankind,” and when it bursts, it could cut the stock market in half, he told CNBC’s “Futures Now” Thursday.

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