The parts hang all together; nor can one be touched without affecting the rest, in a greater or less degree.

But at the same time, it must be observed, that none of these parts or principles, however useful, are so accurately adjusted, as to keep precisely within those bounds in which their utility consists; but they are, all of them, apt, on every occasion, to run into the one extreme or the other.

One would imagine, that this grand production had not received the last hand of the maker; so little finished is every part, and so coarse are the strokes with which it is executed.

Thus, the winds are requisite to convey the vapours along the surface of the globe, and to assist men in navigation: but how oft, rising up to tempests and hurricanes, do they become pernicious?
Rains are necessary to nourish all the plants and animals of the earth: but how often are they defective?
how often excessive?
Heat is requisite to all life and vegetation; but is not always found in the due proportion.

On the mixture and secretion of the humours and juices of the body depend the health and prosperity of the animal: but the parts perform not regularly their proper function.