# On the Vital Principle/Book 3/Chapter 7

Knowledge is, when active, identical with that which is known; but knowledge, in potentiality, pre-exists in the individual, and yet, strictly speaking, it does not pre-exist, as all products are from a being in reality. Now, it is the object of perception, which appears, by its agency, to create sensation from the sensibility which is in potentiality; for it suffers neither impression nor change. So that this is a different kind of motion; for motion was said to be the act of something incomplete; but an act in an absolute sense is different, as it is the act of something complete. Thus, a simple sensation is like to a simple affirmation or a single idea; and as the impression may be grateful or painful, it is, as it were, affirmative or negative, and it bids ​to flee from or pursue after something; and perceptions of pain and pleasure emanate from the sentient medium in its relation to good or evil, in so far as things may be one or other. So actual flight from something is identical with actual appetite, as the fugitive impulse does not differ from the appetitive stimulus, for they differ neither from one another nor from the sentient medium; and yet they do differ in mode of being. Images belong, naturally, to the thinking, as sensations do to the sentient principle; and as it may affirm or deny that anything is good or bad, it bids to flee from or pursue after it. The Vital Principle, therefore, never thinks without an image; as the air has made the pupil what it is, the pupil something else, and so with the hearing; but the last term is one, as the mean, to which belong several modes of being, is one.
It has already been said by what faculty the mind discerns that sweet differs from hot, but yet it may be spoken of again here. It is then an unit of some kind; and an unit in the sense of a limit, for it is as an unit and a limit in the relation, considered analogically and numerically, which the unit bears to the limit. What matters it, besides, whether our doubt is as to how the faculty judges of things, generically, the same, or opposite, as white and black ?
Let A = white be in relation to B = black, and let C be to D as A is to B, and so reciprocally; if C, D be ​properties of some one body they will be as the properties A, B, and the body will be one and the same with the other, although not the same in the mode of being; and the same reasoning will hold good, of course, though A be = sweet and B = white. Thus, the cogitative faculty dwells upon ideas in images, and by images, independently of sensation, it in some way determines what ought to be pursued after or fled from; but, when acted upon by images, it is moved to think, and, perceiving the beacon to be on fire and moving, it comprehends, by that common property (motion), that an enemy is at hand. Sometimes, too, by images or thoughts present in Vital Principle, that faculty, as if seeing, calculates and orders things future in their relation to things present; and when it suggests that something is grateful or hurtful, it bids to pursue after or flee from it, as its biddings always tend to action. And with respect to all which pertains to inaction, the true and the false are in the same genus with the good and bad; but with this difference, that the former have an absolute, and the latter only a relative signification. The mind dwells upon abstractions, so termed, as it thinks upon a snub nose: in so far as it is a nose of that character it cannot be thought upon abstractedly, but in so far as it is concave the mind can, by thinking intensely upon the form, realise to itself the nose without the flesh in which the form is embodied. Thus, too, the mind ​thinks upon mathematical questions as abstractions, although they are not really so, when they are thought upon.
In fine, the mind when thinking, is, in act, the thing thought upon. It shall hereafter be considered whether or not it can be admitted that the mind, without being itself apart from magnitude, can comprehend abstractions.

## Notes

Layout 2
​Note 1, p. 165. Images belong, naturally, to the thinking principle, &c.] This very suggestive comparison between intellectual and sentient perceptions, seems, even in the absence of knowledge of the brain, to assume that ​practical thoughts must be derived from the senses, and, therefore, through a sensorium; and as impressions may be genial or otherwise, the faculties suggest pursuit or flight. The practical mind, in fact, never thinks without an image which acts, in its turn, so to say, upon it, as the air, which has been impressed by colour, does upon the pupil and the pupil upon something else (that is, the retina), and so sound upon the hearing; but the last term, that is, the visual or auditory sense, is one, as the mean or medium, however modified in condition, is one. It will be evident, with but little consideration, that the obscurity which is palpable in the succeeding passages is occasioned by the absence of the brain, and can be cleared away only by its introduction; and that, with it, the analogies of unit and limit acquire some kind of signification.
Note 2, p. 166. Thus the cogitative faculty dwells, &c.] Aristotle seems here to consider images or thoughts, present in memory, as necessary to ratiocination, and he has elsewhere said that an individual without senses could neither learn nor understand; but he is evidently alluding to a higher faculty than the sensibility, and which is able, by abstract reasoning, to draw, from present appearances or images, conclusions as to future occurrences, and, by that prevision, to determine what should or should not be done.
Note 3, p. 166. And with respect to all which, &c.] This passage seems, although obscure from its brevity, to ​imply that without action, when thoughts are not carried out that is, there can for us be neither good nor bad, as these are relations pertaining to individuals, and dependent, not upon any universal law but, upon social institutions; but that truth, being the same for ever, is, even when not exercised, in an absolute relation to all men, and in opposition to all falsehood.
Note 4, p. 166. The mind dwells upon abstractions, &c.] The term abstractions here, as in an earlier passage, signifies mathematical questions, which, from not being referrible to any particular body, admit of being treated as such; and so a snub-nose, as the realisation of a particular form, may, by that form apart from matter, be regarded as an abstraction. The argument is then resumed that the mind, when thinking, is, when active or in act, the subject thought upon. The closing passage, by its questioning whether "the mind, without being itself immaterial, can comprehend abstractions," seems to militate against the arguments adduced to prove that it is impassive and homogeneous, freed, that is, from all the conditions of matter; but it is yet doubtful where (whether or not in "the metaphysics") this argument may, according to promise, have been continued.