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river themselves, as at first. I confirm this by another experiment. After attentively surveying a fine statue, I close my eyes. What follows? The same object continues, without any difference bu that it is less distinct than formerly.* This indistinct secondary perception of an object, is termed an idea. And therefore the precise

*This experiment, which every one may reiterate till entire satisfaction be obtained, is of greater importance than at first view may appear; for it strikes at the root of a celebrated doctrine, which for more than two thousand years has misled many philosophers. This doctrine, as delivered by Aristotle, is in substance, "That of every object of thought there must be in the mind some form, phantasm, or species; that things sensible are perceived and remembered by means of sensible phantasms, and things intelligible by intelligible phantasms; and that these phantasms have the form of the object without the matter, as the impression of a seal upon wax has the form of a seal without its matter." The followers of Aristotle add, "That the sensible and intelligible forms of things, are sent forth from the things themselves, and make impressions upon the passive intellect, which impressions are perceived by the active intellect." This notion differs very little from that of Epicurus, which is, "That all things send forth constantly and in every direction, slender ghosts or films of themselves (tenuia simulacra, as expressed by his commentator Lucretius); which striking upon the mind, are the means of perception, dreaming," &c. Des Cartes, bent to oppose Aristotle, rejects the doctrine of sensible and intelligible phantasms; maintaining, however, the same doctrine in effect, namely, That we perceive nothing external but by means of some image either in the brain or in the mind: and these images he terms ideas According to these philosophers, we perceive nothing immediately but phan tasms or ideas; and from these we infer, by reasoning, the existence of ex ternal objects. Locke, adopting this doctrine, employs almost the whole o his book about ideas. He holds, that we cannot perceive, remember, no imagine any thing, but by having an idea or image of it in the mind. He agrees with Des Cartes, that we can have no knowledge of things external, but what we acquire by reasoning upon their ideas or images in the mind; taking it for granted, that we are conscious of these ideas or images, and of nothing else. Those who talk the most intelligibly explain the doctrine thus: When I see in a mirror a man standing behind me, the immediate object of my sight is his image, without which I could not see him: in like manner, when I see a tree or a house, there must be an image of these objects in my brain or in my mind: which image is the immediate object of my perception; and by means of that image I perceive the external object.

One would not readily suspect any harm in this ideal system, other than the leading us into a labyrinth of metaphysical errors, in order to account for our knowledge of external objects, which is more truly and more simply accounted for by direct perception. And yet some late writers have been able to extract from it death and destruction to the whole world, levelling all down to a mere chaos of ideas. Dr. Berkeley, upon authority of the philosophers named, taking for granted that we cannot perceive any object but what is in the mind, discovered that the reasoning employed by Des Cartes and Locke to infer the existence of external objects, is inconclusive; and upon that discovery ventured, against common sense, to annihilate totally the material world. And a later writer, discovering that Berkeley's arguments might with equal success be applied against immaterial beings, ventures still more boldly to reject by the lump the immaterial world as well as the material; leaving nothing in naturo but images or ideas floating in vacuo, without affording them a single mind for shelter or support.

When such wild and extravagant consequences can be drawn from the ideal system, it might have been expected, that no man who is not crazy would have ventured to erect such a superstructure, till he should first be certain beyond all doubt of a solid foundation. And yet upon inquiry, we find the foundation of this terrible doctrine to be no better than a shallow metaphysical argument, namely, "That no being can act but where it is; and consequently, that

and accurate definition of an idea, in contradistinction to an origi nal perception, is, "That perception of a real object which is raised in the mind by the power of memory." Every thing we have any knowledge of, whether internal or external, passions, emotions, thinking, resolving, willing, heat, cold, &c., as well as external objects, may be recalled as above by the power of memory.*

it cannot act upon any subject at a distance." This argument possesses indeed one eminent advantage, that its obscurity, like that of an oracle, is apt to impose upon the reader, who is willing to consider it as a demonstration, because he does not clearly see the fallacy. The best way to give it a fair trial, is to draw it out of its obscurity, and to state it in a clear light, as follows: "No subject can be perceived unless it act upon the mind, but no distant subject can act upon the mind, because no being can act but where it is: and, there fore, the immediate object of perception must be something united to the mind so as to be able to act upon it." Here the argument is completed in all it parts; and from it is derived the supposed necessity of phantasms or ideas united to the mind, as the only objects of perception. It is singularly un lucky, that this argument concludes directly against the very system of which it is the only foundation; for how can phantasms or ideas be raised in the mind by things at a distance, if things at a distance cannot act upon the mind? I say more, that it assumes a proposition as true, without evidence, namely, That no distant subject can act upon the mind. This proposition undoubtedly requires evidence, for it is not intuitively certain. And, therefore, till the proposition be demonstrated, every man without scruple may rely upon the conviction of his senses, that he hears and sees things at a distance.

But I venture a bolder step, which is, to show that the proposition is false. Admitting that no being can act but where it is, is there any thing more simple or more common, than the acting upon subjects at a distance by intermediate means? This holds in fact with respect both to seeing and hearing. When I see a tree, for example, rays of light are reflected from the tree to my eye, forming a picture upon the retina tunica; but the object perceived is the tree itself, not the rays of light, nor the picture. In this manner distant objects are perceived, without any action of the object upon the mind, or of the mind upon the object. Hearing is in a similar case; the air, put in motion by thunder, makes an impression upon the drum of the ear; but this impression is not what I hear, it is the thunder itself by means of that impression.

With respect to vision in particular, we are profoundly ignorant by what means and in what manner the picture on the retina tunica contributes to produce a sight of the object. One thing only is clear, that as we have no knowledge of that picture, it is as natural to conceive that it should be made the instrument of discovering the external object, and not itself, as of discovering itself only, and not the external object.

Upon the chimerical consequences drawn from the ideal systern, I shall make but a single reflection. Nature determines us necessarily to rely on the veracity of our senses; and upon their evidence the existence of external objects is to us a matter of intuitive knowledge and absolute certainty. Vain therefore is the attempt of Dr. Berkeley and of his followers to deceive us, by a metaphysical subtilty, into a disbelief of what we cannot entertain even the slightest doubt. [See also Beattie's Moral Science, 104-106.]

From this definition of an idea, the following proposition must be evident, That there can be no such thing as an innate idea. If the original perception of an object be not innate, which is obvious; it is not less obvious, that the idea or secondary perception of that object cannot be innate. And yet, to prove this self-evident proposition, Locke has bestowed a whole book of his treatise upon Human Understanding. So necessary it is to give accurate definitions, and so preventive of dispute are definitions when accurate. Berkeley has taken great pains to prove another proposition equally evident, That there can be no such thing as a general idea: all our original percep tions are of particular objects, ard our secondary perceptions or ideas must be equally so.

Dr.

15. External objects are distinguishable into simple and complex. Certain sounds are so simple as not to be resolvable into parts; and so are certain tastes and smells. Objects of touch are for the most part complex: they are not only hard or soft, but also smooth or rough, hot or cold. Of all external objects, visible objects are commonly the most complex: a tree is composed of a trunk, branches, leaves it has color, figure, size. But as an action is not resolvable into parts, a perception, being an act of sense, is always simple. The color, figure, umbrage of a spreading oak, raise not different perceptions: the perception is one, that of a tree, colored, figured, &c. A quality is never perceived separately from the subject; nor a part from the whole. There is a mental power of abstraction, of which afterward; but the eye never abstracts, nor any other external sense.

16. Many particulars besides those mentioned enter into the perception of visible objects, motion, rest, place, space, time, number, &c. These, all of them, denote simple ideas, and for that reason admit not of a definition. All that can be done is to point out how they are acquired. The ideas of motion and of rest are familiar even to a child, from seeing its nurse sometimes walking, sometimes sitting the former it is taught to call motion; the latter, rest. Place enters into every perception of a visible object: the object is perceived to exist, and to exist somewhere, on the right hand or on the left, and where it exists is termed place. Ask a child where its mother is, or in what place it will answer readily, she is in the garden. Space is connected with size or bulk: every piece of matter occupies room or space in proportion to its bulk. A child perceives that when its little box is filled with playthings, there is no room or space for more. Space is also applied to signify the dis tance of visible objects from each other; and such space accordingly can be measured. Dinner comes after breakfast, and supper after dinner a child perceives an interval, and that interval it learns to call time. A child sometimes is alone with its nurse; its mother is sometimes in the room; and sometimes also its brothers and sisters: It perceives a difference between many and few; and that difference it is taught to call number.

17. The primary perception of a visible object is more complete, lively, and distinct than that of any other object. And for that reason, an idea, or secondary perception of a visible object, is also more complete, lively, and distinct than that of any other object. A fine passage in music may for a moment be recalled to the mind with tolerable accuracy: but after the shortest interval, it becomes no less obscure than the ideas of the other objects mentioned.

18. As the range of an individual is commonly within a narrow space, it rarely happens that every thing necessary to be known comes under our own perceptions. Language is an admirable con

trivance for supplying that deficiency; for by language every man's perceptions may be communicated to all: and the same may be done by painting and other imitative arts. The facility of com

munication depends on the liveliness of the ideas; especially in language, which hitherto has not arrived at greater perfection than to express clear ideas: hence it is, that poets and orators, who are extremely successful in describing objects of sight, find objects of the other senses too faint and obscure for language. An idea thus acquired of an object at second-hand, ought to be distinguished from an idea of memory, though their resemblance has occasioned the same term idea to be applied to both; which is to be regretted, because ambiguity in the signification of words is a great obstruction to accuracy of conception. Thus Nature hath furnished the means of multiplying ideas without end, and of providing every individual with a sufficient stock to answer, not only the necessities, but even the elegancies of life.

19. Further, man is endued with a sort of creative power: he can fabricate images of things that have no existence. The materials employed in this operation are ideas of sight, which he can take to pieces and combine into new forms at pleasure: their complexity and vivacity make them fit materials. But a man hath no such power over any of his other ideas, whether of the external or internal senses: he cannot, after the utmost effort, combine these into new forms, being too obscure for that operation. An image thus fabricated cannot be called a secondary perception, not being derived from an original perception: the poverty of language, however, as in the case immediately above mentioned, has occasioned the same term idea to be applied to all. This singular power of fabricating images without any foundation in reality, is distinguished by the name imagination.

20. As ideas are the chief materials employed in reasoning and reflecting, it is of consequence that their nature and differences be understood. It appears now that ideas may be distinguished into three kinds: first, Ideas derived from original perceptions, properly termed ideas of memory; second, Ideas communicated by language or other signs; and third, Ideas of imagination. These ideas differ from each other in many respects; but chiefly in respect of their proceeding from different causes: The first kind is derived from real

*["Memory is double:-not only do I remember that I have been in the presence of a certain object, but I represent to myself this absent object as it was, as I have seen, felt, and judged it:-the remembrance is then an image. In this last case, memory has been called by some philosophers imaginative memory. Such is the foundation of imagination; but imagination is something more still.

"The mind, applying itself to the images furnished by memory, decomposes them, chooses between their different traits, and forms of them new images. Without this new power imagination would be captive in the circle of memory."] -Cousin's Lect. on the Beautiful, p. 135.

existences that have been objects of our senses: language is the cause of the second, or any other sign that has the same power with language; and a man's imagination is to himself the cause of the third. It is scarce necessary to add, that an idea, originally of imagination, being conveyed to others by language or any other vehicle, becomes in their mind an idea of the second kind; and again, that an idea of this kind, being afterwards recalled to the mind, beco nes in that circumstance an idea of memory.

21. We are not so constituted as to perceive objects with indifference these with very few exceptions appear agreeable or disagreeable; and at the same time raise in us pleasant or painful emotions. With respect to external objects in particular, we distinguish those which produce organic impressions, from those which affect us from a distance. When we touch a soft and smooth body, we have a pleasant feeling as at the place of contact; which feeling we distinguish not, at least not accurately, from the agreeableness of the body itself; and the same holds in general with regard to all organic impressions. It is otherwise in hearing and seeing: a sound is perceived as in itself agreeable, and raises in the hearer a pleasant emotion; an object of sight appears in itself agreeable, and raises in the spectator a pleasant emotion. These are accurately distinguished: the pleasant emotion is felt as within the mind; the agreeableness of the object is placed upon the object, and is perceived as one of its qualities or properties. The agreeable appearance of an object of sight is termed beauty; and the disagreeable appearance of such an object is termed ugliness.

22. But though beauty and ugliness, in their proper and genuine signification, are confined to objects of sight, yet in a more lax and figurative signification, they are applied to objects of the other senses: they are sometimes applied even to abstract terms; for it is not unusual to say, a beautiful theorem, a beautiful constitution of government.

23. A line composed by a single rule [or prescribed mode], is perceived and said to be regular: a straight line, a parabola, an hyperbola, the circumference of a circle, and of an ellipse, are all of them regular lines. A figure composed by a single rule, is perceived and said to be regular: a circle, a square, a hexagon, an equilateral triangle, are regular figures, being composed by a single rule, that determines the form of each. When the form of a line or of a figure is ascertained by a single rule that leaves nothing arbitrary, the line and the figure are said to be perfectly regular; which is the case of the figures now mentioned, and the case of a straight line and of the circumference of a circle. A figure and a line that require more than one rule for their construction, or that have any of their parts left arbitrary, are not perfectly regular: a parallelogram and a rhomb are less regular than a square; the parallelogram being subjected to no rule as to the length of sides, other than that

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