Would Someone Please Explain to Paul Ryan How This "Insurance" Stuff Works?

by Dan SavageRyan: The whole idea of Obamacare is...the people who are healthy pay for the...sick. It's not working, & that's why it's in a death spiral pic.twitter.com/ztTXrn7bpH— David Mack (@davidmackau) March 9, 2017
Dear Paul,
Car insurance premiums paid by drivers who don't get in crashes subsidize the care and/or legal liabilities of drivers who do get in crashes. Lucky, un-crashed people pay for unlucky, crashed people. That's not a "fatal conceit." That's literally how car ins