 Despite the synchronic character of his famous Principle, Clifford's view is not merely that we must be in a certain state at the precise time at which we form a belief. Rather, the obligation always and only to believe on sufficient evidence governs our activities across time as well. With respect to most if not all of the propositions we consider as candidates for belief, says Clifford, we are obliged to go out and gather evidence, remain open to new evidence, and consider the evidence offered by others. The diachronic obligation here can be captured as follows: