 One early semantic picture for the latter camp was that a sentence of the form \(\OB (q\mid p)\) is true at a world \(i\) iff the \(i\)-best \(p\)-worlds are all \(q\)-worlds. \(\OB q\) is then true iff \(\OB (q\mid \top),\) and so iff all the unqualifiedly \(i\)-best worlds are \(q\)-worlds (B. Hansson 1969). Note that this weds preference-based semantic orderings with dyadic conditional  obligations.[53]  This reflects a widespread trend. Factual detachment does not work in this case, since even if our world is an I-don’t-go-help-world, and the best among the I-don’t-go-help-worlds are I-don’t-call-worlds, it does not follow that the unqualifiedly best worlds are I-don’t-call-worlds. In this example, these authors would maintain that the unqualifiedly best worlds are both I-go worlds and I-call worlds, and the fact that I won’t do what I’m supposed to do won’t change that.