Miracles 3.9 Lewis distinguishes two senses of because: Sense 1: Cause and Effect an event chain the earlier event "Grandfather ... ate lobster yesterday" and the later event: "Grandfather is ill today ... " are related by the latter event being caused by the prior event. Sense 2: Ground and Consequent is a logical relation. Grandfather has not gotten up today (the Ground) therefore he must be ill (the Consequent). The observation is the basis for our conclusion. Lewis's point is that they are "wholly distinct" relations, although they can be used together and thus confused.