A reader:

You wrote:
“I don’t know enough about Milton Friedman’s biography, but I’d guess he thinks his philosophy
cannot be separated from the empirical arguments which support it.”
This is exactly Friedman’s position, which he spells out in
a 1975 letter to Friedrich Hayek, which can be found at the Hoover
Institute — and in my files (I’ve got a copy).
It turns out Friedman didn’t understand Hayek’s position.
Hayek believe the _empirical_ facts of the division of knowledge
and the limits of the mind _empirically_ made socialism _empirically_
impossible. For Hayek that is the most decisive and powerful
empirical place to go to show what socialism would mean for the poor
and everyone else (plus a bit of empirical and logical stuff about
capital and value theory).
Friedman, who had a degree in statistics (he’d planned to go into
the insurance industry) thought the empirics was all in the “data” you
historically collected over time (NOTE that this does not give you
empirical scientific laws, as you get with Hayek).
Sorry to nerd you out like this.
– greg ransom, editor of the Hayek Scholars Page

And:

Jonathan says that “true conservatives” oppose government intrusionon ideological grounds first
and only secondarily or marginally on empirical grounds.<<
Conservatives who are economists have put together an _empirical_
science called economics which leads them to empirical judgments about
what will work empirically and what won’t. Leftist call this science
an “ideology” — the word as currently used goes back to Marx.
Jonathan is simply using the old Marxist technique to smear successful
science. This strategy almost always works for leftists among leftists.