11. THE last general head of these errors comprehends such, as follow from the various sects of false philosophies; which this author divides into three sorts, the sophistical, empirical, and superstitious[26]. By the first of these he means a philosophy built upon speculations only without experiments[27]; by the second, where experiments are blindly adhered to, without proper reasoning upon them[28]; and by the third, wrong opinions of nature fixed in mens minds either through false religions, or from misunderstanding the declarations of the true[29].
12. THESE are the four principal canals, by which this judicious author thinks, that philosophical errors have flowed in upon us. And he rightly observes, that the faulty method of proceeding in philosophy, against which he writes[30], is so far from assisting us towards overcoming these prejudices; that he apprehends it rather suited to rivet them more firmly to the mind[31]. How great reason then has his Lordship to call this way of philosophizing the parent of error, and the bane of all knowledge[32]? For, indeed, what else but mistakes can so bold and presumptuous a treatment of nature produce? have we the wisdom necessary to frame a world, that we should think so easily, and with so slight a search to enter into the most secret springs of nature, and discover the original causes of things? what chimeras, what monsters has not this preposterous method brought forth? what schemes, or what hypothesis’s of the subtilest wits has not a stricter enquiry into nature not only overthrown, but manifested to be ridiculous and absurd? Every new improvement, which we make in this science, lets us see more and more the weakness of our guesses. Dr. HARVEY, by that one discovery of the circulation of the blood, has dissipated all the speculations and reasonings of many ages upon the animal oeconomy. ASELLIUS, by detecting the lacteal veins, shewed how little ground all physicians and philosophers had in conjecturing, that the nutritive part of the aliment was absorbed by the mouths of the veins spread upon the bowels: and then PECQUET, by finding out the thoracic duct, as evidently proved the vanity of the opinion, which was persisted in after the lacteal vessels were known, that the alimental juice was conveyed immediately to the liver, and there converted into blood.