ABSTRACT
The effort to identify a single diacritical marker for science, like the quest to find some privileged type of knowledge more generally, must be inconclusive, because of the irreducible variety of values, norms, and motives that organize all kinds of action, contemplative as well as conative or practical. Moreover, the connection to defensible purposes provides a central criterion for assessing each cognitive form and indeed for deciding what order of claim to the production of privileged knowledge it may now be said to possess. To acknowledge that fact, however, is not necessarily to assert that there are no forms of privileged knowledge. Rather, it is to state that sincere adherence to a single criterion of the generically scientific is to commit oneself to a polemical position that invalidates the legitimate claims of other kinds of knowledge. The record of responses to that quest provides a summary of major moments in the history of human speculation.
