A lightening, or clearing, of the mental state in the hours or days before death, particularly in those delirious, is occasionally noted by those caring for the dying. Similar phenomena have been described in the natural world and in classical literature. This brief period of lucidity is generally followed by a rapid terminal decline. The author reports on his experience with six cases illustrating this phenomenon. The increasing use of palliative sedation may diminish the possibility of lightening up before death occurring. The theoretical concepts of Hughlings Jackson may provide an explanation for this phenomenon.