Note x — Chapter III

The following quaint apology for our senses at the expense of our understanding may be new to the majority of my readers:—

"We have seen two notorious instances of sensitive deception, which justifie the charge of Petron. Arbiter.

And yet to speak properly, and to do our senses right, simply they are not deceived, but only administer an occasion to our forward understandings to deceive themselves: and so though they are some way accessory to our delusion; yet the more principal faculties are the Capital offenders. Thus if the Senses represent the Earth as fixt and immoveable; they give us the truth of their Sentiments: To sense it is so, and it would be deceit to present it otherwise. For (as we have shewn) though it do move in itself; it rests to us, who are carry'd with it.... But if hence our Understandings falsely deduct, that there is the same quality in the external impressor; 'tis, it is criminal, our sense is innocent. When the Ear tingles, we really hear a sound: If we judge it without us, it's the fallacy of our Judgments. The apparitions of our frighted Phancies are real sensibles: But if we translate them without the compass of our Brains, and apprehend them as external objects; it's the unwary rashness of our Understanding deludes us. And if our disaffected Palates resent nought but bitterness from our choicest viands, we truly tast the unpleasing quality, though falsely conceive it in that, which is no more then the occasion of its production. If any find fault with the novelty of the notion; the learned St. Austin stands ready to confute the charge: and they who revere Antiquity, will derive satisfaction from so venerable a suffrage. He tells us, Si quis remum frangi in aquâ opinatur, et, cum aufertur,integrari; non malum habet internuncium, sed malus est Judex. And onward to this purpose, The sense could not otherwise perceive it in the water, neither ought it: For since the Water is one thing, and the Air another; 'tis requisite and necessary, that the sense should be as different as the medium: Wherefore the Eye sees aright; if there be a mistake, 'tis the Judgement's the Deceiver. Elsewhere he saith, that our Eyes misinform us not, but faithfully transmit their resentment to the mind. And against the Scepticks, That it's a piece of injustice to complain of our senses, and to exact from them an account, which is beyond the sphear of their notice: and resolutely determines, Quicquid possunt videre oculi, verum vident. So that what we have said of the senses deceptions, is rigidly to be charg'd only on our careless Understandings, misleading us through the ill management of sensible informations." Glanvill, Vanity of Dogmatizing. Chap. x. First Ed. p. 91, seq.

The reader may like to consider how far Glanvill's apology for the senses is removed from the following propositions laid down by a recent writer just quoted who thus defends while he limits the veracity of sense-impressions:—

"What we directly apprehend," writes Professor Helmholtz, "is not the immediate action of the external exciting cause upon the ends of our nerves, but only the changed condition of the nervous fibres which we call the state of excitation or functional activity." And further on:—"The simple rule for all illusions of sight is this: we always believe that we see such objects as would, under conditions of normal vision, produce the retinal image of which we are actually conscious. If these images are such as could not be produced by any normal kind of observation, we judge of them according to their nearest resemblance; and in forming this judgment, we more easily neglect the parts of sensation which are imperfectly than those which are perfectly apprehended. When more than one interpretation is possible, we usually waver involuntarily between them; but it is possible to end this uncertainty by bringing the idea of any of the possible interpretations we choose as vividly as possible before the mind by a conscious effort of the will." Helmholtz on The Recent Progress of the Theory of Vision. pp. 230, 31 and p. 307.