THE WORLD IS NOT BENSONHURST, 1948, WHEN I WAS 4.
I was brought up an Orthodox Jew in a Brooklyn of ethnic Jews and Catholics. At Columbia I studied physics during that department's high Chinese-Jewish period. Eventually, at 30, I entered a rather more explicitly Christian world, teaching for four years at the University of Minnesota, one in which the mutual hostility of Protestants and Roman Catholics is often recalled. Many of my students had areligiously-oriented education in undergraduate school, Lutheran or Benedictine or Jesuitical, for example. A familiarity with Scripture, or a Thomistic Aristotelianism, came through in their questions.
Being concerned professionally with how new ideas enter and take over the public arena, I became interested in how Judaism's offshoots, Christianity and Islam, arose and fared in the Antiquity that was Greek and Roman and otherwise pagan--a lacuna in my otherwise fine general education in high school and college. How did a Jewish man become the salvific figure Jesus Christ? And how did this particular Judaic sect become so dominant, its doctrine claiming to be less and less conventionally Jewish? Much of secular history is remarkably Christian (or Whiggish) and consequently unhelpful for my inquiry. The conventional story assumes that the solution is Christianity, and so Judaism becomes a problem in Christian history. 
There are many canonical ways of thinking about and judging public policy and doctrine. Legal and Talmudic interpretation, traditional political theory and ethics, or demography and economics might do. But the policies we select as both good and as worthy of being pursued are it seems not founded directly upon our empirical or theoretical inquiries. We have long-standing commitments to some projects, commitments that are unlikely to be abandoned no matter what inquiry yields.
We know that new ideas and practices in the public arena are never the only or the best solution. They are often ignored; and they are always succeeded by other ideas. It is better to see the workings of putative salvific figures, and of conversion to new beliefs, as aspects of avowedly secular history in which there is no transcendent salvation. In a history without salvation, new ideas and discoveries have an ironic quality. The ideas are no more the solution than is Jesus of Nazareth or Sabbatai Sevi for present-day Jews.
My concern is not only with the success and succession of ideas but with how those ideas are employed. Systematic knowledge of the world is useful for public policy-making because it suits our practical instruments for action and helps us achieve particular political goals. For example, economic theory and incentives may be preeminent in our thinking if the process of the market is important as apolitical instrument. But such economic theory will be less useful if our politics and political theory pays more attention to substantive questions of political stability and legitimation, family relationships, satisfying work, and a meaningful life. 
There is a gap between what we actually do and believe and their deductive and empirical foundations, much as there is a gap between what we are actually given and our desires. Understanding such a gap is perhaps the deep motivation for my engagement with a sequence of German thinkers, from Kant to Heidegger (and proverbially, from Luther to Hitler). Eugen Rosenstock-Huessy notes that "All German philosophy is but an attempt to remove the kingdom of heaven to a transcendental space and time which is inaccessible for mortals, but which nevertheless stimulates us constantly to make anew (though hopeless) effort in the direction of the ideal." 
Kant argued in The Critique of Judgement (1790) that the gap is bridged by a "common sense" and by a set of conventions we share in our community. We appeal to that sharedness when we make an argument, so demanding that others will appreciate the force of our reasons. …