  The existence of such feels may seem to some to mark the threshold for states or creatures that are really conscious. If an organism senses and responds in apt ways to its world but lacks such qualia, then it might count as conscious at best in a loose and less than literal sense. Or so at least it would seem to those who take qualitative consciousness in the “what it is like” sense to be philosophically and scientifically central (Nagel 1974, Chalmers 1996).