Can we have one without the other? Possibly not. These may be polar opposites which only find expression when both are possible.
General Relativity and Quantum Mechanics are at polar odds with each other, and many physicists are trying to reconcile them in a grand unified theory. Perhaps they are not meant to be unified. Maybe unity is found elsewhere.
We live at the crossroads of a dual-nature. How well we bear that cross, integrating these dualities into one, may define our life.