 Posing a clear question involves grasping its possible answers and in science, this is informed by identifying experiments that can provide evidence for such answers. The emphasis on necessary and sufficient conditions in our two questions indicates how to empirically test specific proposals. To test sufficiency, one would aim to produce or modulate a certain neural state and then demonstrate that consciousness of a certain form arises. To test necessity, one would eliminate a certain neural state and demonstrate that consciousness is abolished. Notice that such tests go beyond mere correlation between neural states and conscious states (see  section 1.6  on neural correlates and sections  2.2,  4 and  5  for tests of necessity and sufficiency).