If Thomas's approach to the constitution is 'even more radical' I guess we are to take it that Scalia is a radical. To a liberal like Lithwack I suppose this is true but others might be skeptical of the claim.
Milton Friedman famously self-described his own views - now commonly held to be mainstream but which were not long ago considered by Lithwackians as beyond the pale- as 'radical' (as opposed to liberal) meaning I think that he wanted to upturn what had become the unquestioned status quo in economic theory and return it to the precepts made famous by Adam Smith. In this way I suppose Scalia might be seen as a radical but only because those around him have made their oiwn radical deformations of the court appear to be a state of nature to liberals....