317. III. EVERYTHING OF WHICH MAN HAS PERSUADED HIMSELF AND WHICH HE HAS CONFIRMED IN HIMSELF REMAINS WITH HIM AS HIS OWN. It is believed by many that no truth can be seen by man except from proof; but this is false. In the civil and economic affairs of a kingdom or of a republic what is useful and good cannot be seen unless several statutes and ordinances in force there are known, and in judicial matters unless the laws are known; and in the things of nature, as physics, chemistry, anatomy, mechanics and other subjects, unless one has been instructed in the sciences. But in matters purely rational, moral and spiritual, truths are apparent in their own light, provided man has from a right education become in some degree rational, moral and spiritual. This is because every man as to his spirit, or that which thinks, is in the spiritual world as one among those who are there; and consequently he is in spiritual light which enlightens the interiors of his understanding, and as it were dictates. For spiritual light in its essence is the Divine Truth of the Lord's Divine Wisdom.
Hence it is that man can think analytically, form conclusions about what is just and right in judicial matters, can see what is honourable in moral life and what is good in spiritual life, and also can see many truths which do not become obscured unless by the confirmation of falsities. What is good and true in the spiritual life man sees almost in the same way as he sees the mind (animus) of another in his face, and perceives his affections from the tone of his voice, with no other knowledge than what is inherent in everyone. Why should not a man see in some measure from influx the interior things of his life, which are spiritual and moral, when there is no animal which does not know by influx the things necessary for it, which are natural? A bird knows how to build nests, lay its eggs, hatch its young and knows its own food; besides other wonderful things which are called instinct.