This week, I did something very dumb: I got into a Twitter fight with a bunch of venture capitalists.

The proximate cause of my fight was <a href="this">http://blogs.wsj.com/digits/2015/03/10/secretive-bitcoin-startup-21-reveals-record-funds-hints-at-mass-consumer-play/">this <em>Wall Street Journal</em> article</a> about 21, a secretive Bitcoin start-up that has raised $116 million in venture capital, with much of it coming from Silicon Valley mega-firm Andreessen Horowitz.