Providence has so ordered it, that a state of rest and inaction, however it may flatter our indolence, should be productive of many inconveniences; that it should generate such disorders, as may force us to have recourse to some labor, as a thing absolutely requisite to make us pass our lives with tolerable satisfaction; for the nature of rest is to suffer all the parts of our bodies to fall into a relaxation, that not only disables the members from performing their functions, but takes away the vigorous tone of fibre which is requisite for carrying on the natural and necessary secretions. At the same time, that in this languid in active state, the nerves are more liable to the most horrid convulsions, than when they are sufficiently braced and strengthened. Melancholy, dejection, despair, and often self-murder, is the consequence of the gloomy view we take of things in this relaxed state of body. The best remedy for all these evils is exercise or _labor_; and labor is a surmounting of _difficulties_, an exertion of the contracting power of the muscles; and as such resembles pain, which consists in tension or contraction, in everything but degree. Labor is not only requisite to preserve the coarser organs, in a state fit for their functions; but it is equally necessary to these finer and more delicate organs, on which, and by which, the imagination and perhaps the other mental powers act. Since it is probable, that not only the inferior parts of the soul, as the passions are called, but the understanding itself makes use of some fine corporeal instruments in its operation; though what they are, and where they are, may be somewhat hard to settle: but that it does make use of such, appears from hence; that a long exercise of the mental powers induces a remarkable lassitude of the whole body; and on the other hand, that great bodily labor, or pain, weakens and sometimes actually destroys the mental faculties. Now, as a due exercise is essential to the coarse muscular parts of the constitution, and that without this rousing they would become languid and diseased, the very same rule holds with regard to those finer parts we have mentioned; to have them in proper order, they must be shaken and worked to a proper degree. SECTION VII. EXERCISE NECESSARY FOR THE FINER ORGANS.