In philosophical terms, the opposite of rationalism is not irrationalism but empiricism, that is, a willingness to form beliefs on the basis of experience rather than from a priori deduction. Empirical evidence never yields the dogmatic certainty that accompanies logical deduction.

The term "rational" and its variants (rationality, rationalism) are used in a lot of contexts in economic debate, both positively and negatively, but nearly always sloppily or dishonestly. A specimen I've seen on more occasions than I can count is the line (usually presented with a sense of witty originality) "if you are opposed to economic rationalism, you must be in favor of economic irrationalism"... I've come to the conclusion that the word "rational" has no meaning that cannot better be conveyed by some alternative term and that the best advice is probably to avoid it altogether.

It seems strange to make a priori arguments about the relative performance of governments and the markets in health care when there is so much empirical evidence.

Throughout the history of the Internet, most of the innovation has come as a by-product of efforts to facilitate communication within social groups of various kinds (academics, bloggers, peer-to-peer file sharing), rather than as the result of profit-oriented investment. Rather than taking the lead, the business and government sectors have adopted innovations developed in Internet communities, and realised significant productivity gains as a result.

In philosophical terms, the opposite of rationalism is not irrationalism but empiricism, that is, a willingness to form beliefs on the basis of experience rather than from a priori deduction. Empirical evidence never yields the dogmatic certainty that accompanies logical deduction.