body, when the whole body has been in a state of inaction; a sensation of fatigue may be more particularly realized in particular members, as the arms, feet, legs, eyes, when these members have been particularly overworked.

Men accustomed to labor are most liable to weariness from inaction; men accustomed to inaction are most liable to fatigue from labor. Were it not for this sense, we should be both without the means of judging whether we have reached or passed the due measure of bodily exertion, and without any admonition to prompt us to that measure of exercise and of rest which our well being demands.

If any object to assigning to this sense a specific existence in the mental constitution, I would ask, What shall we do with it? Are we conscious of this class of sensations? Yes. Are they of sufficient importance to deserve notice? Certainly. Do all sensations imply a sense? As truly as any mental act implies a power to that act. To what, then, shall we refer the sensations in question? To the sense of smell? We do not smell weariness and fatigue. Taste? We do not taste them. Touch? We do not touch them. Sight? We do not see them. Hearing? We do We do not hear them. Temperature? They are neither hot, cold, nor lukewarm. We must, then, refer them to a specific sense. The mind is so constituted, that, in certain states of the body, sensations of this class are realized, as truly and determinately as, in other states of it, are those of smell or of hearing.

III. THE SENSE OF PLEASURE AND PAIN.

These also, being counterparts, may be referred to the same sense. It may be questioned, whether we have any distinct sense of pleasure and pain, or whether these sensations are not referable to the individual or combined action of the other senses. The former seems the more philosophical supposition. All will admit that the pleasure we realize in smelling a rose is a different thing from the sensation of smell. The smell is one

thing, the pleasure is another; yet both are sensations The term sensual pleasure, as distinguished from purely mental pleasure, conveys a distinct idea to all minds. The calm and continued pleasure

so constant that

we scarcely notice it, except when interrupted- arising from a state of health and the free and full play of all the bodily functions, and the painful uneasiness resulting from a state of debility or disease, are sensations too marked not to be referred to a specific source. Who can reasonably doubt that there is a specific provision in the mental constitution for these sensations?

What has been said of pleasure is equally true of pain. The smell of a disagreeable odor is one thing, the pain attending that smell another; yet both are real sensations. Both afford us distinct cognitions. "To expe. rience those states of the bodily organs which are adapt ed to produce pain is one thing, and to experience pair another; the former is continued during certain periods the latter occasional or remitted. What is generally considered continual pain consists usually of a series of painful sensations, more or less protracted, and separated from each other by longer or shorter intervals of repose or relief from the occurrence of other mental exercises."*

It is the obvious design of pain to admonish us of something wrong in our system, and incite us to correct it, and to avoid its recurrence. In this view, the sense of pain, as well as of pleasure, is a great blessing.

It is perhaps unnecessary to add, that all kinds and degrees of the sensations of pleasure and of pain, which we receive through the body, are referable to this sense. Whether, then, it is of sufficient importance to deserve a name and a place, let humanity, in the multitude of her pleasures and pains, judge.

*Critical Exposition of Mental Philosophy, by Leicester A. Sawyer, New Haven edition, 1839.

IV. THE SENSE OF APPETITE.

By the sense of appetite, I designate that in our constitution which gives rise to hunger, thirst, and sexual desire. For popular convenience, we speak of thirsting for water and of hungering for food; but both hunger and thirst, as also the other instinctive desires or cravings of nature, now considered, are referable to the same generic sense of appetite. This sense is variously developed at different periods of growth, according to the demand for it.

To those who may object to there being a particular sense of appetite, and who would refer all appetite to ordinary sensations of pain seeking relief, I would say, Is not that uneasiness which occasions desire for food, drink, &c., unlike any other? Do not all other uneasy or painful sensations tend to destroy this desire? The pain (if so they choose to call that which I call appetite) which gives rise to this, desire implies a natural and healthy state; all other pain implies an unnatural and diseased state. The latter directly destroys, the former directly produces, the desire in question. The one belongs to man in innocence and soundness; the other pertains to him in sinfulness and disease. I infer, therefore, a specific provision in our constitution for the sensations in question. In other words, that we have a sense of appetite, which is as truly a part of our original constitution as the sense of smell or of taste. The importance of this sense is certainly not inferior to that of any pertaining to our system.

"The ultimate purpose of the sensations connected with the appetites is evidently the voluntary preservation of life, and the continuance and multiplication of the different orders of voluntary beings. They serve as the exciting causes of desires and actions, which are necessary to the attainment of these ends, and are an essential part of the nature of all voluntary beings. Man is not alone in the exercise of them. All the other tribes of voluntary beings which are subject to his dominion, or divide with him the empire of the world, are capable of similar exercises."*

* Sawyer's Mental Philosophy, p. 30.

Before leaving the consideration of the additional senses noticed in this chapter, I would remark, that the various sensations to which they give rise furnish us with a vast fund of primary knowledge; that they minister largely to our enjoyment or our suffering, according as they are rightly used or abused; and that they are the occasions of numerous desires and aversions, from which spring those affections and volitions which are the subject matter of moral philosophy. To that department a more extended notice of the nature and uses of appetite must be referred. It would seem that sensations of this class have not hitherto received sufficient notice, owing, probably, to the difficulty of defining and classing them.

QUESTIONS ON CHAPTER III.

What is meant by a sense of Temperature? What comparison is made between this and the sense of smell? Where is the organ of this sense located? What would be our experience without it? Why may weariness and fatigue be referred to the same sense? From what does weariness arise? From what fatigue? With what is weariness attended? With what fatigue? Where is the organ of this sense located? Where and when may a sensation of weariness be realized? A sensation of fatigue? What is said of men accustomed to labor, and the reverse? What would be our condition without this sense? State the substance of the reply to those who object to assigning to it a specific existence in the mental constitution. Why may pleasure and pain be referred to the same sense? What question may be raised here? Which of the two suppositions seems most philosophical? What reasons are given? What is the obvious design of pain? What is meant by the sense of appetite? What reasons are given in answer to those who deny that we have a specific sense of appetite? What importance is assigned to the sensations due to the senses here considered?

CHAPTER IV.

SENSATION.

HAVING Considered those mental susceptibilities or powers, together with their organs, which are the sources of sensation, we are prepared to notice the various sensa tions themselves to which they give rise.

A SENSATION IS A MENTAL

AFFECTION IMMEDIATELY RE

SULTING FROM A CHANGE IN AN ORGAN OF SENSE.

Mental affections, not originating through organs of sense, such as love, joy, hatred, are sometimes called sensations, but not with philosophical accuracy. They are mental feelings, but not sensations. The term sensation is, by the best authorities, restricted to those mental affections which are directly due to the organs of sense. When something is said to have produced a great sensation among a people, as the news of a victory or a defeat, -the expression is to be understood as popular and not philosophical language.

Under the head of sensations, I include all the mental affections of which the senses are the direct subjective cause. It is as philosophical to speak of sensations of pleasure and pain, of weariness and fatigue, of heat and cold, as of smell, or of touch, or of taste. Those who al low only five senses are puzzled to know where to place the first class of the above sensations.