Fletcher notes that previously work on quantum gravity has focused on reduction and emergence of properties as opposed to intertheoretic reduction.  He’d like to help correct this omission.  His topic here is causal set theory.  He’d like to show that the “Hauptvermutung” or primary conjecture of causal set theory has, as yet, no rigorous formulation, but that paying attention to observables may help show the way to such a formulation.