affections, and therefrom recognizes and sees them.  Previously there is a kind of veil interposed, that does, indeed, transmit to love the light of heaven; yet inasmuch as the love does not in that degree love its consort, wisdom, it does not receive it, yea, may even contradict and rebuke it when it returns from its elevation.  Still man flatters himself that the wisdom of his understanding may be made serviceable as a means to honor, glory, or gain.  Then man gives self and the world the first place, and the Lord and heaven the second, and what has the second place is loved only so far as it is serviceable, and if it is not serviceable it is disowned and rejected; if not before death, then after it.  From all this the truth is now evident, that love or the will is purified in the understanding if they are elevated together.

420.  The same thing is imaged in the lungs, whose arteries and veins correspond to the affections of love, and whose respirations correspond to the perceptions and thoughts of the understanding, as has been said above.  That the heart’s blood is purified of undigested matters in the lungs, and nourishes itself with suitable food from the inhaled air, is evident from much observation. (1) That the blood is purified of undigested matter in the lungs, is evident not only from the influent blood, which is venous, and therefore filled with the chyle collected from food and drink, but also from the moisture of the outgoing breath and from its odor as perceived by others, as well as from the diminished quantity of the blood flowing back into the left ventricle of the heart. (2) That the blood nourishes itself with suitable food from the inhaled air is evident from the immense volumes of odors and exhalations continually flowing forth from fields, gardens, and woods; from the immense supply of salts of various kinds in the water that rises from the ground and from rivers and ponds, and from the immense quantity of exhalations and effluvia from human beings and animals with which the air is impregnated.  That these things flow into the lungs with the inhaled air is undeniable:  it is therefore undeniable also that from them the blood draws such things as are useful to it; and such things are useful as correspond to the affections of its love.  For this reason there are, in the vesicles or innermost recesses of the lungs, little veins in great abundance with tiny mouths that absorb these suitable matters; consequently, the blood that flows back into the left ventricle of the heart is changed into arterial blood of brilliant hue.  These facts prove that the blood purifies itself of heterogeneous things and nourishes itself with homogeneous things.  That the blood in the lungs purifies and nourishes itself correspondently to the affections of the mind is as yet unknown; but in the spiritual world it is very well known, for angels in the heavens find delight only in the odors that correspond to the love of their wisdom, while the spirits in hell find delight only