AS there are numerous sorts of _Diseases_, so there are numerous manners or ways of the production of Diseases; and those Diseases that are produced by _Conceit_, are first occasioned by the Rational Corporeal Figurative Motions: for, though every several Conceit, or Imagination, is a several Rational Corporeal Figurative Motion; yet, every Conceit or Imagination doth not produce a Sensitive Effect: but in those that do produce a Sensitive Effect, it is the Conceit or Imagination of some sorts of Diseases; but in most of those sorts that are dangerous to Life, or causes Deformity: The reason is, That as all the Parts of Nature are Self-knowing, so they are Self-loving: Also, Regular Societies beget an united Love, by Regular Agreements, which cause a Rational Fear of a disuniting, or dissolving; and that is the reason, that upon the perception of such a Disease, the Rational, through some disorder, figures that Disease; and the Sensitive Corporeal Motions, take a pattern from the Rational, and so the Disease is produced. The Tenth Part. CHAP. I. Of FEVERS. Some are of opinion, That all, or, at least, most Diseases, are accompanied, more or less, with a _Feverous Distemper_: If so, then we may say, A _Fever_ is the _Fundamental Disease_: but, whether that Opinion is true, or no, I know not; but I observe, there are many sorts of Fevers, and so there are of all other Diseases or Distempers: for, every alteration, or difference, of one and the same kind of Disease, is a several sort. As for Fevers, I have observed, there are Fevers in the Blood, or Humours, and not in any of the Vital Parts; and those are ordinary Burning-Fevers: and there are other sorts of Fevers that are in the Vital Parts, and all other Parts of the Body, and those are _Malignant Fevers_; and there are some sorts of Fevers which are in the Radical Humours, and those are _Hectick Fevers_; and there are other sorts of Fevers that are in those Parts, which we name the _Spiritous Parts_. Also, all _Consumptions_ are accompanied with a Feverish Distemper: but, what the several Figurative Motions are of these several sorts of Fevers, I cannot tell. CHAP. II. Of the PLAGUE.