lungs give the capacity of separate or circumstantial action to the organs of the body, and take up or absorb the propulsions of the heart by the formal attractions of the organs themselves: they enfranchise the organs from the general force and form, as the understanding enfranchises the man from the domination of the surrounding universe. The understanding dictates precise motives into the soul from without, and by the bonds of truth, which are its membranes, acts specifically upon the affections. The lungs, through their universal connections in the body, carry distinct motions into the system, and operate physically upon the vital parts. The understanding admits invigorating elements of truth from heaven: the lungs receive fresh air from the atmospheres. The understanding, obeyed in action, conciliates the earth with heaven, and joins spiritual powers to bodily works: the lungs, in their healthy operation upon an obedient frame, mediate between the brain and the body, and draw the animal spirit of the former into the blood and muscles of the latter. But, not to extend too far this parallelism of uses, we may state in brief, that the understanding distributes the affections into series, and provides for the separate and alternate, as well as combined, action of these series; and that analogously the lungs dispart the natural motions into free series, moment these into expansion and contraction, and also provide a general movement into which all particular actions cease as their office expires.
Now, then, so far as this has gone, the lungs are to the body what the understanding is to the mind. Quoad understanding, the mind cannot pass really out of its own sphere, or grapple with the material body; but it descends in its form, and adopts the prepared lungs, which receive because they express its form of motion, and, in performing their functions, carry out its designs in the lower world. This, then, is the correspondence between the two, that they are co-ordained, and the higher finds in the lower an answerable minister for extending its effects to a new goal. Similarity of end ensures correspondence; also the virtual presence of the superior in the inferior, and reciprocal conjunction of each with each. And this endures so long as the lower can serve the higher,
