that persons unaccustomed to analyze their thoughts, are apt to suppose that attention is nothing more than a single act.

Even among those, who have never made a single inquiry concerning the nature of their minds, attention seems sufficiently understood. Every one knows what it is to attend; he is convinced that it is an exertion which he may make or not as he pleases, and the continuance of which depends entirely on his will.

To make that effort of the mind, which we name attention, seems easier to some than it is to others; but it is an effort that all are capable of making, and the facility of doing so will be increased in proportion to the frequency and continuance of their attempts.

Of Sensation.

By sensation is meant, that state of the mind which is generally the consequence of some external object's making an impression on any one of our senses; but it proceeds also from other causes. Sensation, considered in itself, is simply a state of feeling. It has been commonly named a faculty of the mind, but it is in its nature rather passive than active. A man cannot avoid having sensations, nor can he voluntarily produce them in himself, except in as far as he may be said to do so, by applying to his senses

such things as generally cause them. Sensation does not necessarily lead to the belief of something external; on the contrary, our sensations are often very lively when nothing external appears to produce them. It seems natural, however, when we feel in any particular way, to attempt a discovery of the cause of our feeling: but our remarks on this part of the subject have been in a great measure anticipated in the observations on the senses.

Sensation arises from three causes;-from the impression of external objects on the organs of sense; from the appetites; and from the passions. We know from experience, that when any thing external is brought within a certain distance of us, or, in some instances, into direct contact with our organs of sense, that a change of state is produced in our minds; and to this state we apply the term sensation. We discover that the qualities of objects have thus an effect on our senses, and that these senses, by some mode of communication to which we are wholly strangers, convey their impressions to the mind; but this is all we know of the matter.

Our appetites also cause sensations: when we are hungry or thirsty, an uneasy sensation exists, but ceases on our partaking of food or of drink. This, like many other things, is known only as a fact; for why the want of food should produce, and the supply of it remove, this uneasy sensation, eludes our inquiry. It is, however, a wise appointment of Pro

vidence, to remind us that food is necessary for the support of our bodies, and to induce us to abstain when we have satisfied our hunger.

The third source of sensations is the passions. It is the mind that feels; and sensation, as we have seen, generally originates in some impression made on the organs of sense, and through that medium, communicated to the mind; but in the sensation occasioned by the passions, it is otherwise. There is here a sort of re-action. Passion has been explained as a particular state of the mind, resulting from the manner in which it is affected by external objects, actions, or events; or by the view that an individual takes of his own conduct, or of the conduct of others. Here, it is not necessarily implied, that an impression is first made on the organs of sense. of mind denominated passion, may be the consequence of a person's thinking on his own conduct, or on that of another, or of his anticipation of any thing that may happen to him. The mind being affected, produces an effect on the body, and this again affects the mind. Thus the apprehension of danger produces fear; fear produces a shrinking or withdrawing of the body from the object feared; and this state of the body, by the re-action mentioned above, increases the weakness and confusion of the mind.

The state

To the sensations experienced when the mind is in that state denominated passion, it is more common and more proper to apply the term feeling than sens

ation; as the latter is apt to bring with it the idea of the senses, and from the preceding observations, it is obvious, that the mind may feel without the intervention of the senses.

Sensations of a most painful kind are frequently occasioned by disease. Rheumatism, toothach, and gout, are often so acute, as nearly to prevent the suffererer from exercising reason. That the immaterial thinking being, to which we give the name of mind, should be so affected by any change in the body, is, in this instance, as incomprehensible as the cause of any other sensation that has been named. Experience and research teach the physician, that certain obstructions, occasioned he knows not how, produce acute pain, and that these obstructions may be removed, and the pain alleviated, by the judicious application of medicines; but to explain why, in such cases, the mind should be so affected by any derangement of the corporeal system, baffles his skill. That some things precede others, by which they are uniformly followed, is a matter of belief; and to such antecedents and consequents, we rightly give the names, cause and effect; but who can tell, why that which he calls a cause, should produce that which he calls its effect?

Happy the man who sees a God employed
In all the good and ill that chequer life !
Resolving all events, with their effects

And manifold results, into the will

And arbitration wise of the Supreme.

*

Forth steps the spruce philosopher, and tells
Of homogeneal and discordant springs
And principles; of causes, how they work
By necessary laws their sure effects;
Of action and re-action. He has found
The source of the disease that nature feels,
And bids the world take heart and banish fear.
Thou fool! will thy discovery of the cause
Suspend the effect, or heal it? Has not God

Still wrought by means since first he made the world?
And did he not of old employ his means

To drown it? what is his creation less
Than a capacious reservoir of means,

Formed for his use, and ready at his will?

Go! dress thine eyes with eye salve; ask of him,

Or ask of whomsoever he has taught;

And learn, though late, the genuine cause of all.

Of Perception.

:

To perceive, in one application of the word, is nearly synonymous with to see; and hence in speaking of any object of sight, we are sometimes said to perceive it, and sometimes to see it but the verb perceive, and the substantive perception, are not confined to objects of sight alone; they are metaphorically applied to the discovery of the qualities of things in general. Perception is therefore used to