The phrase 'Hard Problem of Consciousness' isn't meaningless. It's contemporary academic jargon in the philosophy of mind, introduced by the Australian philosopher David Chalmers in 1995. (He's currently teaching at the ANU in Canberra.) See the IEP article on the 'Hard Problem' at this link: http://www.iep.utm.edu/hard-con/ Chalmers' website is here: http://consc.net/chalmers/ The IEP article summarizes the problem this way: In other words, the claim that a 'hard problem" exists in the first place, seems to basically be a non-physicalist challenge to functionalist philosophies of mind. It isn't difficult to see why it's of great interest to philosophical idealists and to individuals of a "spiritualist" persuasion, we might say. A great deal of current discussion in the philosophy of mind currently revolves around this problem.