Proposition of value versus existential judgment

"James believes that the study of the origin of an object or an idea does not play a role in the study of its value. He asserts that existential judgment, or the scientific examination of an object's origin, is a separate matter from that object's value. One must not consider an object's physical derivation when making a proposition of value. As an example, he alludes to the Quaker religion and its founder, George Fox. Many of the scientists in James' audience, and many today, immediately reject all aspects of the Quaker religion because evidence suggests that Fox was schizophrenic. Calling this rejection medical materialism he insists that the origin of Fox's notions about religion should not come into account when propositioning the value of the Quaker religion. As an aside, many believe El Greco to have suffered from astigmatism, yet no one would dismiss his art based on this medical detail. James proposes, somewhat sarcastically, that his audience's atheism is perhaps a dysfunction of the liver. Some believe science to be superior to religion because of religion's seemingly vain, unfounded, or perhaps insane origin. In his lectures, James asserted that these claims, while perhaps historically or epistemologically interesting, play no role in the separate question of religion's value."

[Wikipedia]