Those unsympathetic to Ryan’s position quickly seized upon the last two sentences as revealing that Ryan simply doesn’t understand the fundamental concept of health care.” The whole idea of Obamacare is the people on the blue side pay for the people on the red side. The people who are healthy pay for the people who are sick,” Ryan said, which: of course. Insurance is always about those who don’t need insurance at the moment paying into the insurance pool for those who do. It’s how insurance works. Insurance companies balance the amount people pay as premiums to allow them to cover the payouts for expenses.

As the Atlantic’s Derek Thompson pointed out, this isn’t only a feature of pooled insurance — it’s a feature of the insurance you yourself pay. “Even a one-person insurance market only works if your in-flow years pay for out-flow years,” Thompson wrote on Twitter. “It’s still ‘healthy-you’ subsidizing ‘sick-you.’ ”

When Ryan says, “It’s not working, and that’s why it’s in a death spiral,” the implication offered is that the “it” refers to the idea of insurance overall and that, therefore, insurance itself necessarily doesn’t work. Which, of course, isn’t the case.

Ryan’s overall presentation of the way Obamacare works is accurate. To offset the costs of having to cover everyone — since Obamacare makes insurers cover even those who are already sick — the system needs young, healthy people to pay in. That’s why there’s a mandate to have coverage, so that there’s enough money coming in to pay for everyone. Those reading Ryan unsympathetically — generally on the basis of the snippet above — see Ryan as simply not understanding that the “fatal conceit” he offers is the core value proposition of insurance.