Joseph Glanvill (1636-1680), Scepsis Scientifica: or, Confest Ignorance, the Way to Science; in an Essay of the Vanity of Dogmatizing and Confident Opinion
, ed. John Owen (London: Kegan Paul, Trench & Co, 1885), pp. 193-195 (from Chap. XXVII):
I expect but little success of all this upon the Dogmatist; his opinion'd assurance is paramount to Argument, and 'tis almost as easy to reason him out of a Feaver, as out of this disease of the mind. I hope for better fruit from the more generous Vertuosi, to such I appeal against Dogmatizing, in the following considerations. That's well spent upon impartial ingenuity, which is lost upon resolved prejudice.
(1.) Opinionative confidence is the effect of Ignorance, and were the Sciolist perswaded so, I might spare my further reasons against it: 'tis affectation of knowledge, that makes him confident he hath it; and his confidence is counter evidence to his pretensions to knowledge. He is the greatest ignorant, that knows not that he is so: for 'tis a good degree of Science, to be sensible that we want it. He that knows most of himself, knows least of his knowledge, and the exercised understanding is conscious of its disability. Now he that is so, will not lean too assuredly on that, which hath so frequently deceived him, nor build the Castle of his intellectual security, in the Air of Opinions. But for the shallow passive intellects, that were never engag'd in a thorough search of verity, 'tis such are the confidents that engage their irrepealable assents to every slight appearance. Thus meer sensible conceivers make every thing they hold a Sacrament, and the silly vulgar are sure of all things. There was no Theoreme in the Mathematicks more certain to Archimedes, than the Earth's immovable quiescence seems to the multitude: nor than did the impossibility of Antipodes, to antique ages. And if great Philosophers doubt of many things, which popular dijudicants hold as certain as their Creeds, I suppose Ignorance it self will not say, it is because they are more ignorant. Superficial pedants will swear their controversal uncertainties, while wiser heads stand in bivio. Opinions are the Rattles of immature intellects, but the advanced Reasons have outgrown them. True knowledge is modest and wary; 'tis ignorance that is so bold, and presuming. Thus those that never travail'd beyond one Horizon, will not be perswaded that the world hath any Countrey better than their own: while they that have had a view of other Regions, are not so confidently perswaded of the precedency of that they were bred in, but speak more indifferently of the laws, manners, commodities, and customs of their native soil: So they that never peep't beyond the common belief in which their easie understandings were at first indoctrinated, are strongly assured of the Truth, and comparative excellency of their receptions while the larger Souls, that have travelled the divers Climates of Opinions, are more cautious in their resolves, and more sparing to determine. And let the most confirm'd Dogmatist profound far into his indeared opinions, and I'le warrant him 'twill be an effectual cure of confidence.