Our knowledge springs from two fundamental sources of the mind; the first is the capacity of receiving representations (receptivity for impressions), the second is the power of knowing an object through these representations (spontaneity [in the production] of concepts).
We have arranged for ourselves a world in which we can live - by positing bodies, lines, planes, causes and effects, motion and rest, form and content; without these articles of faith nobody could now endure life. But that does not prove them. Life is no argument. The conditions of life might include error.
The difference between the actual and the ideal force of man is happily figured in by the schoolmen, in saying, that the knowledgeof man is an evening knowledge, vespertina cognitio, but that of God is a morning knowledge, matutina cognitio.