The document discusses different philosophical approaches to evaluating the validity of statements or propositions based on the types of questions asked. Gottfried Leibniz focuses on rational justification independent of empirical data. John Locke focuses on empirical data and statistical analysis. Immanuel Kant looks for a combination of data and theoretical justification. Georg Wilhelm Friedrich Hegel examines alternative views and the potential for synthesis of ideas. Peter Singer considers whether the right questions are being asked and perspectives considered. Mitroff and Turoff note that each approach reflects a different way of understanding communication and that many more exist.

1. Different questions, different epistemology! Suppose we are given a set of statements or propositions by some individual or group which pretend to describe some alleged "truth." Then each of our philosophical systems can be simply differentiated from one another in terms of the kind of characteristic question(s) that each would address either to the statement itself or to the individual (group) making the statement or assertion. Each question in effect embodies the major philosophical criterion that would have to be met before that Inquiring System would accept the propositions as valid or as true.

9. The Problem of Knowledge (Communication Between Disciplines!) Pieter Bruegel: The Tower of Babel 1563)