"Thus the Truth is not introduced into the individual from without, but was within him." If truth was within then there has to be something that which prevents the individual from accessing it entirely. Naturally the truth is going to be an activity of the mind and not that of the brain, or the physical body. For if the two were not disjunct there would then be the necessary requirement of presenting an organ which contained truth, or a collection of organs that contained truth and a bio-physiological network that accessed that organ for truth. So it would also be necessary for an organ to somehow restrict access to the truth organ such that the individual does not know everything. For that is an assumption that man does not know the entire truth. Had he known it all he would have had no need to seek any and the curious nature of man would've never found development. Truth is mind's activity, and mind is assumed disjunct from brain. There has to then be something which prevents the individual from accessing all truth. This is the basis for the existence of religion.