But I cannot forget that, at other times I have been deceived in sleep by similar illusions; and, attentively considering those cases, I perceive so clearly that there exist no certain marks by which the state of waking can ever be distinguished from sleep, that I feel greatly astonished; and in amazement I almost persuade myself that I am now dreaming.
Rene DescartesDivide each difficulty into as many parts as is feasible and necessary to resolve it.
Rene DescartesThe mind effortlessly and automatically takes in new ideas, which remain in limbo until verified or rejected by conscious, rational analysis.
Rene Descartes