ART V. -- INTERNAL SENSES.
28. The internal senses are four in number: the common sense, imagination, the estimative faculty, and sensitive memory. -- A sensitive being not only perceives the sensible qualities of bodies, but it distinguishes them from one another by a single act, it perceives the acts of the senses and the sensitive state that accompanies them whether of pleasure or pain. But for this a sense is requisite to which the perceptions of all the external senses are referred as to their common centre, an internal sense which can thus cognize the acts of the senses. This internal sense is called the common sense. But the sensible being must apprehend the sensible object, not only when it is present, but also when it is absent. Hence it stands in need of a faculty which can preserve and reproduce the images already received. This faculty is imagination. The sensitive being might be able to seek or to shun not only those things that produce agreeable or disagreeable sensations in it, but also those that may be advantageous or hurtful to it in other respects. Hence it must be able to cognize their useful or harmful properties, to preserve and reproduce the perception of these properties, so that in the absence of useful objects they may direct themselves towards them. This it does by means of the estimative faculty which perceives these properties, and the sensitive memory which preserves this perception. Memory recalls all past sensations and their objects just as they occurred, in which it differs from imagination.
29. It is an error to deny the common sense and say, with Rosmini, that the soul has through its essence the feeling of its sensations; or, with Condillac, that each sense perceives its own sensations; or, with other philosophers, that the sensations of each sense are perceived by the intellect. -- The opinion of Rosmini (1797-1855) is false, for the soul operates through its faculties and never directly through its essence. The opinion of Condillac is also false, because a simple sensation and the perception of the sensation are two things essentially distinct and cannot be referred to a single sense; also because supposing each sense can perceive its own sensations, it can neither perceive the sensation of another sense nor its proper sensible. Now, the fact that the sensations of all the senses are perceived by a single faculty cannot be denied, for we compare our various sensations. Lastly, those philosophers who say that man has no need of an internal sense, because his intellect can perceive the acts of the external senses, are also in error; for sensation is a sensitive act; the perception of the sensation, therefore, supposes a sensitive operation, and consequently a sensitive faculty. The existence of the internal sense called sensus communis is shown not merely by reason, but also to some extent by physiology; for it testifies that the nerves of all the external senses diverge from a common source, where they unite as in their centre. This one point of reunion of the sensitive nerves may be regarded as the organ of common sense.
30. The common sense{1} has three functions: 1. It perceives and distinquishes the perceptions of the different senses; 2. It perceives the different states of the sentient being, whether of pleasure or pain, accompanying or following these perceptions; i.e., it acts the part of sensitive consciousness; 3. It perceives the proper and the common sensibles. -- 1. The perceptions of all the senses are referred to tbe common sense as to their proper faculty. Since, then, they must all be cognized by this central sense, it must evidently be capable of distinguishing them from one another, but it cannot know them as different. As each sense can perceive only its own proper sensible, it cannot distinguish it from the other sensibles; for to distinguish two things, both must be known. 2. The second function of the common sense is to perceive the act of the senses and the state that accompanies and follows the act. The object of each sense is one; but the objects of the external senses are outside the sentient subject; these senses, moreover, cannot perceive their own sensations. For the species impressa, or form of the object impressed on sense and through which it perceives the object, is too close to sense to be seen by it or perceived. To perceive the sensation of each sense is proper to the common sense, just as to perceive the objects that impress the senses is proper to the external senses. 3. The common sense has a third function, which is to perceive the common sensible. Since this sensible should be apprehended by several senses to be duly known, it is manifestly the proper object of common sense, since the latter perceives the sensations of all the particular senses. For instance, to know motion accurately, we must perceive both by touch and by sight: but these distinct perceptions can be perceived by the common sense alone.
31. Imagination or fancy is an internal sense which preserves the images or sensible species of objects already perceived by the external senses, and reproduces them in the absence of their objects. -- The existence of this faculty is attested by experience, which shows us the sensitive subject reproducing images of the sensible objects which it once perceived; but this it could not do if it had not preserved the images of these objects. By this faculty the soul retains the images of whatever was perceived by the external senses. They are like the glass of the camera obscura, which preserves the images only as long as the objects are present; imagination is like the photographic plate, which preserves the images indefinitely. As this faculty only preserves images of objects already perceived, it is evident that where a sense is wanting, the corresponding image in the imagination will also be wanting. Hence a man born blind can form no image of color. Some philosophers, and among them Cousin, have wrongly regarded imagination as an inventive faculty that can produce images of objects not previously perceived. Although imagination can, it is true, form images of objects not existing in nature, yet it can do so only by means of objects already perceived by the senses whose images it can divide or multiply, contract or distend, arrange or disturb, in various ways. But imagination not only preserves the sensible images, it can also reproduce them, and in these images it then contemplates the objects themselves, not in the state of immobility as on a photographic plate, but as they are in reality, moving, acting, and living, though not in the same exactitude with which they were first perceived; for this belongs to memory. In the animal, the reproduction of the images corresponds exactly to the reality perceived before by the senses; man can besides unite or separate the images in his imagination and combine them in diverse ways. Thus, from the image of gold and the image of a mountain, he forms the one image of a mountain of gold. In this way the artist becomes capable of producing masterpieces, the poet creates his fictions, the scientist conceives hypotheses by which he supplies the facts which nature hides from him. This special power of imagination man possesses, not as properly belonging to the sensitive life, but in consequence of the perfection which the sensitive life in him receives from the intellectual life, a redundancy flowing over, as it were, from the higher faculty to that which is immediately beneath it.
32. Association of images is subject to laws which refer partly to the nature of the soul and partly to tbe nature of the images. -- Association of images, which modern philosophers improperly name association of ideas, depends partly on the nature of the soul. Thus in virtue of the unity of the soul, just as the phantasm, through the action of intellect in man, influences his free will and necessarily determines the sensitive appetite in the animal, so does the will in man, and the sensitive appetite in the animal, call up the image or phantasm in the imagination.
Association of images depends also partly upon the nature of the images, which, according to the relations existing among them, are reduced to three categories: those of similarity, contrast, and contiguity whether of space or time. These relations are at times unperceived, but for all that they are real.
33. The imagination in man should be regulated and prudently directed by the will, and this by intellect. -- The imagination plays a very important part in man, since it furnishes his intellect with material for its operations. Hence it is necessary so to regulate it that it may be of great service in the acquisition of truth. In the first place, since it is an organic faculty having a corporeal organ, it is evidently more or less perfect according to the physical organism of the individual and the external influences that modify that organism. Hence man should guard against all those influences which injure the orderly exercise of the imagination and from which he can withdraw himself, In the second place, since the will exercises a direct action on the imagination, man should guide his imagination by his will enlightened by reason, and constantly subject it to the control of the real; otherwise the imagination may by compounding and dividing images give a factitious existence to deceitful phantoms, and thus become the source of many errors for the intellect, and consequently of much wrongdoing for the will.
34. The estimative faculty is an internal sense which perceives and distinguishes things not perceived by the other senses, such as the useful or hurtful. -- The existence of this sense is attested by experience, for we see that animals seek what is useful to them and avoid what is hurtful. It is also proved by reason. In order to preserve its being the animal must perceive not only what is agreeable or disagreeable, but also what is useful or harmful. It is by this faculty that the sheep knows that the wolf is his enemy, that the bird chooses the straw required for its nest. To this faculty, also, must be ascribed the marvellous skill and sagacity shown by animals in self-preservation and self-defence.
Man possesses the estimative faculty as well as the brute; but in man it is more perfect because influenced by intelligence. The animal perceives the useful or the hurtful in a thing by natural instinct; man, as an effect of a sort of comparison. Thus the estimative faculty, which in the brute is analogous to reason, is in man called particular reason, the cogitative faculty, or passive intellect.
35. Sensitive memory is an internal sense that preserves and reproduces the cognitions acquired through the senses, and reproduces the sensible images with the knowledge of their perception in past time. -- A sensitive being does more than perceive in sensible objects what is useful or hurtful, for it also preserves these perceptions. Thus a dog shuns the places where he was beaten. This faculty of preserving and reproducing the perceptions of the other sensitive faculties is called sensitive memory.{2} It differs from imagination, for it reproduces the cognitions of sensible objects with the condition of past time in which they took place, and also recognizes now as once perceived the perceptions recalled; while the imagination reproduces images simply and neither with any determination of time nor in the order of their first appearance. For an act of memory, therefore, it does not suffice that the image perceived in time past be reproduced, but there must be also the knowledge that it was perceived in past time. This apprehension of time, though more noble than that of sensible qualities, is yet limited by two points{3} of a given time, and is determinate and particular. Hence it cannot be the object of intellect, which perceives only the universal as its proper object or object per se, the individual per accidens. Sensitive memory exists both in the brute and in man, as experience proves; but in man, sensitive memory, besides recalling the past, may also deduce from what it recalls a series of connected events. And, as a child holding one end of the thread easily unwinds the spool, so man sees in his memory a long series of events and consequences which a first thought has recalled. This operation is called remniscence, and demands also the exercise of reason.
36. The efficiency of memory depends partly on nature and partly on the mnemonic art. This art has four laws; 1. The representation by similitudes of the objects to be retained; 2. A methodical classification of the objects; 3. An effort to retain them; 4. Continued reflection on the objects. -- Readiness of memory depends first of all on nature. Since memory is an organic faculty, it is evident that the more perfect the organ, the more perfect also will be the faculty. Hence in men the degrees of perfection of memory are as various as the organisms themselves, and these degrees vary even in the same individual according to diversity of age and of organic conditions. But man's memory may also be cultivated and helped by art. For, unlike the brute, which remembers only from natural means, and is determined by physical causes, man remembers not merely in consequence of physical causes, but also with the help of artificial means, which he uses at will.
The first of these means is the representation by similitudes of the objects to be retained. The use of these similitudes will be the more efficient in proportion to their more striking character. Thus in order to recall a great grief, it may be fixed in the memory under the image of a sword. -- The second means is a methodical classification of the objects which we wish to recall. This means is based on the very nature of the mind, which passes from one remembrance to another in virtue of the numerous relations existing among things. Nothing in the universe is isolated; so also in the mind, all its cognitions are bound together, and form by their connection a sort of network, so that one thread cannot be touched without affecting all the others through their relation more or less direct with the part affected. Thus is explained the extreme ease with which the mind passes from one object to another without the bidding of the will, and even in spite of the will. But, if the association of images often takes place in an involuntary manner, it may also be regulated by reflection and directed by the will. This association is based either on purely accidental relations or on logical relations. The former are chiefly those of similarity, contrast, and contiguity in space and time. It is especially by these that children retain, and hence they have a very superficial memory. The principal logical relations are those of principle and consequence, of cause and effect, of means and end, of substance and accident. By these relations the memory brings back within itself the real natural connections of things, it acquires consistency, strength, and unity, and the collection of its recollections is raised to the dignity of science. This, however, is the effect, not of sensitive but of intellectual memory. -- The third mnemonic means is attention to the object and an effort to fix it in the mind. This effort impresses things deeply in the memory, and thus enables it to recall them with ease. -- The fourth means is continued reflection on the object to be retained. We easily recall what we have well considered. Reflection makes our recollection clear and more distinct; it supplies in advanced years the force and intensity which the newness of the object gives to the recollections of the early years of life.
ART. VI. -- THE APPETITIVE FACULTIES. -- SENSITIVE APPETITE.
37. Sensitive appetite is a tendency to good perceived by the senses. -- The tendency of a being is proportioned to its nature. A sensitive being knows through the senses the sensible objects necessary for preserving its existence. Hence it has a natural tendency to seek sensible goods and be united with them. This tendency is called sensitive appetite.
38. Sensitive appetite is divided into two distinct faculties: Concupiscible appetite and irascible appetite. -- Concupiscible appetite is a faculty by which the animal is led to seek what is useful to it, and to shun what is harmful. Irascible appetite is a faculty by which the animal is roused to acquire a good that is difficult to attain, and to remove any evil that would destroy this good or prevent its attainment. By his concupiscible appetite, a dog seeks proper nourishment and avoids what is injurious; by his irascible appetite he is angered and attacks the animal that tries to deprive him of his food.
These are two distinct faculties, for it often happens that they are opposed to each other. Thus anger takes away the need of sleep, as, in turn, the want of rest lessens the heat of anger. At times the closest relations exist between the irascible appetite and the concupiscible; the former may even be regarded as the defender of the latter, since it combats whatever opposes the good sought by the concupiscible appetite, or whatever causes the evil that it shuns. Hence all the movements of the irascible appetite begin from those of the concupiscible, and are referred to the same.
39. A sensitive being when urged on by its appetite transports its body from one place to another. The faculty by which it does this is called locomotive faculty. -- Descartes and his school denied this faculty. He attributed locomotion in the animal to the perfection of its bodily mechanism,{4} and in man to the action of the will. But reason and experience prove the existence of this faculty. For when an animal apprehends a useful or a hurtful object, it has need of a power to approach the one and withdraw from the other; and, in fact, we see that this does happen. It is evident that this faculty is distinct both from the sensitive appetite and the will, for we often shun the sensible good which the appetite craves, and, again, are often unable to produce the motion which the will desires. Like all the other sensitive faculties, it is organic, that is, it resides in an organ and cannot operate without the organ.
ART. VII. -- THE INTELLECTIVE FACULTIES. -- THE INTELLECT.
40. The proper object of the intellect, the intelligible, is the immaterial, the essence of things. -- As the proper object of the intellect is such because of its relation to the intellect, it is rightly called the intelligible. It is the immaterial, the essence of things. For intellect, as the name indicates, is a faculty which penetrates the inner nature of things, that by which they are what they are, viz., their essences. It is without reason that certain philosophers have denied the possibility of knowing the essences of things, and by essences have consequently understood whatever is unknown to us in things. The essences of things are known to us, since we define things and specify them; for they can be defined and specified by their essences only. More than this, essence cannot be known merely in part, for it is indivisible; to know only a part of it, is to be ignorant of it.{5}
41. The proper object of intellect is the immaterial and universal. Its adequate object is entity, whatever is or can be. Its proportionate object, in its actual condition, is the essence of sensible things. -- Every faculty is specified by its actions and its object. Since the intellect performs operations that exceed the power of matter, since they attain to the immaterial and the spiritual, it must itself as the cause of these operations be spiritual. The adequate object of intellect is that which it can apprehend, if it be considered in its own nature. Now, since the intellect is a spiritual faculty and can have a mode of existence independent of matter, it can know every entity, that is, truth. But if the intellect be viewed as a faculty that requires a previous operation of the sensitive powers in order to act, its proportionate object is the essence of sensible things.
42. The intellect is an inorganic faculty, and hence needs no organ for its action. -- Since the object of the intellect is the essence of things, and essence is always immaterial, we know the intellect must likewise be immaterial{6} and independent in its operation of any bodily organ.
43. Since the intellect is an inorganic faculty, the system of phrenology must be considered absurd. -- Phrenologists, headed by Gail (1758-1828) and Spurzheim (1776-1832), regard all the faculties of the soul, sensitive, intellectual, and moral, as residing in bodily organs. They teach that protuberances exist on the surface of the brain and the skull, that each of these is the organ of one of the soul's faculties, and that in proportion as the protuberances are more or less developed, the faculty is also more or less developed. The number of these faculties varies with each phrenologist. Gall allows twenty-seven; Spurzheim, thirty-seven. This theory, if consistent, must end in materialism and fatalism. It is, furthermore, contradicted by experience, which time and again has shown how slight is the relation between this or that protuberance and the corresponding faculty. It is contradicted by science, which proves that there is no constant relation between the protuberances of the skull and the surface of the brain.{7}
44. An abstractive power must be allowed in the soul. --Every being must have in its nature whatever is required for its proper operation. But the proper operation of the human intellect in its present condition has for its first and immediate object the essence of sensible things. Now, since this essence is individualized in the concrete conditions that environ it, it cannot be apprehended by the intellect, which is an inorganic faculty, unless it be stripped of its individuating conditions. Therefore, that the soul may apprehend the essence of sensible things, it must have a faculty capable of ideally separating the essence from its individuating notes. This faculty is called active intellect (intellectus agens).
45. The abstraction of the essence from its individual conditions does not entail any error in cognition. -- A cognition is false when we affirm of an object what does not belong to it, or deny of it what belongs to it. Thus the intellect, viewing the essence in itself abstracted from individual conditions, would err were it to affirm that the essence actually exists in the object separated from these individual conditions. But, since it is restricted to contemplating the essence by itself without any affirmation, and not considering it as really apart from its individuating notes, the abstraction which it makes no more implies error than does silence imply deceit.
46. The abstraction of the essence is possible, whether we consider the abstracted essence in itself, or the condition of the intellect making the abstraction. -- Although the essence cannot exist physically without an individual determination, yet in itself it does not imply a necessary existence in this or that individual; otherwise it could never be found in any otber than this individual, and consequently there could be but one individual in each species. But this is evidently false in regard to sensible objects. Therefore there is nothing in the essence to prevent its being abstracted from the individual in which it subsists, that is, its being considered apart. As to the intellect, if in the act of intellection it must be conformed to the object which it cognizes, it is by no means necessary that it be conformed to it as to the mode of cognizing. Thus, if the mode of existence of the essence is concrete in the real order, nothing prevents its being abstracted in the ideal order.
47. The act of abstraction is prior in nature, but not in time, to that of intellection. -- When two forces concur to the production of one effect, their operation must be simultaneous; for every concurrence, while it does not exclude priority of nature, yet implies simultaneity of time. But the abstractive faculty and the faculty that perceives essence concur in the production of the single effect of intellective knowledge of the essence of material things: the first faculty abstracting the essence, and the second perceiving it. Therefore the act of abstraction is only in nature prior to the act of intellection.
48. The power that abstracts the essence is distinct from that which perceives the essence. -- When two actions are exercised upon a single object in two ways specifically distinct, these two actions must be specifically distinct, and consequently not reducible to the same power; but to abstract the essence and to perceive it are two acts specifically distinct; therefore they demand two distinct powers. Besides, the essences of sensible things are not actually intelligible; but it is only actual being that can effect the passage of an entity from potentiality to act; hence the soul requires besides the faculty by which it comprehends the intelligible, and which is necessarily in potentiality with respect to all intelligibles, a faculty which when in act renders the essences of sensible things actually intelligible, by disengaging them from the material conditions in which they exist. The Schoolmen call this faculty the active intellect (intellectus agens); the other faculty, the possible intellect (intellectus possibilis).
49. For the production oJ the act of intellection, intelligible species are required, or likenesses of the intelligible object, which inform the cognizing intellect. -- Intelligible species (species intelligibilis) is a likeness of the intelligible object, which informs the intellect, and by means of which it can cognize the object. It is without ground that modern philosophers have denied the existence of intelligible species. To acquire knowledge, it is necessary that the object known enter in some way the subject knowing. But it cannot be said that the subject knowing contains already in itself the object known, and in the act of cognition does nothing but contemplate it: for this would identify the subject knowing and the object known. Hence it must be admitted that the object known is communicated to the subject knowing. But it cannot he communicated in its physical substantiality, because it exists outside the subject knowing. Hence it can be communicated to the subject knowing only by means of a representation of itself, and this is called the intelligible species. The intelligible species is named by the Scholastic philosophers the impressed species (species impressa), if it is considered as simply received by the intellect, and as the medium by which the object determines the intellect to the cognitive act. It is called the expressed species (species expressa), if it is considered as the effect in the intellect of the action of intellect after perceiving the impressed species, which action produces complete cognition.
50. The intelligible species is not that which the intellect knows, but that by which it knows. -- If the intelligible species were the object known, it would necessarily constitute the term of the intellective act; but since it is a form inhering in the intellect, it must be apprehended by a reflex act; therefore it is only in reflex cognition that it is the object known. In direct cognition it is the means by which the intellect knows.{8}
51. The act of intellection resulting after the impression of the intelligible object on the intellect by means of the impressed species, is always tke proper act of intellect itself. -- The intellect is called passive or possible, because it is in itself indifferent to this or that act, and consequently requires some determination to be given to it by the object before it can act. Its act is called immanent because it remains in the acting subject and modifies it. It is easily seen (1) that the intellect is first passive, because it is in itself indifferent to knowing this or that object; and (2), because it knows an object only when determined to it by the object, that it is also active, because it is the intellect that knows. The intellective act must be elicited by an intrinsic vital principle. But a faculty is active when it elicits its own acts, and (3) that intellection is an immanent act, because it remains in the faculty, which it ennobles and perfects, and does not change or modify the object. It must be noted that the conditions that make the possible intellect passive are not found in the acting intellect. Hence that intellect is exclusively active.
52. The term of the act of intellection is called the mental word. -- The intellect, after receiving the impressed species, the intelligible species that determines it to action, produces as its term the mental word. This does not really differ from the idea. Yet the word idea expresses the concept of the mind in its relation with the object, while the mental word points out in addition the relation of the concept to the principle whence it proceeds, affirming to itself, as it were, the truth it knows. In its word the intellect perceives the object, just as in a mirror the eye beholds not the mirror, but the object reflected by the mirror. The term of the act of vision, considered as an action, is truly the mirror; but considered as cognition, it is the object. So too the term of the act of intellection considered as the effect of the intellect, is the mental word; but, under the aspect of cognition, it is the object of which the word is as it were the image.
{1} This faculty must be carefully distinguished from that intellectual habit, or "faculty of first principles," explained on p. 135.
{2} Also, and more properly. sensile, memory.
{3} That is, by that moment in the past in which the object was perceived, and by the present moment in which it is recalled.
{4} The opinion that brutes are mere automata is refuted on p. 247. With this falls also the deduction that animals have no power of locomotion.
{5} Hobbes, Locke, Hume, Mill, and Hegel have all either denied the objective reality of essence or at least wrongly defined essence.
{6} Essence is said to be immaterial, not that it is not sometimes joined to matter, but in that it is not necessarily joined to it, and is viewed apart from the individual conditions that determine it in any individual body.
{7} "The fundamental error of the phrenological school lay in the idea that a science of mind can be founded in any shape or form upon the discoveries of anatomy. Their error lay in the notion that physiology can ever he the basis of psychology; and this is an error and a confusion of thought that survives phrenology." -- DUKE OF ARGYLL, quoted in American Catholic Quarterly Review, vol. ii., p. 124.
Yet the influence of body on soul cannot be denied any more than that of soul on body. The most that can be granted is that phrenology may point out certain tendencies in man. These tendencies may be due to heredity or to environment. It fails to appreciate the spirituality of man's soul and his freedom of will.
{8} "The main root of difference between adversaries and ourselves [as to the objective validity of ideas in general], is that they will insist contrary to us, in regarding knowledge as primarily not a knowledge of things but of ideas. They imagine that what we first of all know are always subjective affections as such -- signa ex quibus and signa quibus. . . . The mind perceives through ideas, not in the sense that it looks at ideas first, and then passes on to infer things; but in the sense that the mind, at least under one aspect, begins as a tabula rasa, and only in proportion as it stores itself with ideas is it rendered by them cognizant of objects. . . . A world of misconception would be saved if the right view of the office of ideas were acquired. " -- First Principles, Stonyhurst Series, pp. 825, 826.