things, our belief is controlled; in other words, we naturally and necessarily have a belief in the existence of the things which are perceived. And, in like manner, whenever in the vividness of conceptions there is a near approach to the acknowledged and necessary vividness of the perceptive states of the mind, there is a similar tendency to an affection of the belief. This tendency is realized; in other words, the belief is fully controlled, if the vividness in the two cases is nearly the same.

Now the mere inordinate vividness implies a disordered state of the mind; but, if this be combined with the coexistence of a belief in the actuality of the things conceived of, the disorder is very much increased. It is then that the subject of this unhappy state of things may be said, with something more than a mere metaphorical import of the terms, to live in the midst of a world of his own creating. The mind, exercising itself upon the materials which. the outward world has furnished, reproduces distinct images of things, and, substantiating their reality by the authority of belief, recognises things that are not as in no ways different from things that are. Hence, there are constant mistakes. Things unreal are mistaken for things real. And hence, also, there is frequently a great perplexity of the judgment and the reasoning power. This is obvious, because the judgment and the reasoning power necessarily implicate the ultimate verification of their results with the certainty and reality of their premises; and the source of confidence in the premises has, in a great degree, failed. Not to mention other incidental

evils, which are likely to connect themselves with this peculiar state of mind.

§ 66. Of disordered Conceptions, combined with a disordered State of the outward Organs.

Now if we connect this state of mind, which is sufficiently unfavourable in itself, with a disordered condition of the external senses, the evil will, if possible, be still farther increased. If, for instance, the conception of visible objects be very vivid, and, at the same time, the organ of sight be morbidly susceptible, the vivid conception will be likely, by mere sympathy, to place the optic nerve in the position of actual vision. And the immediate consequence is, that, to all intents and purposes, there is at once a visual perception; and the conception and the perception become merged in each other. Under such circumstances, is it surprising that men should see a variety of phantasms, and find the world peopled with invisible beings?

But it is our wish here to consider this state of mind separate, as much as possible, from mere disordered sensations and perceptions. It is true they are sometimes combined together, perhaps frequently. At the same time, if we wish to get at the sources of insanity and of the modifications of insanity, it seems necessary to give them a distinct consideration. They not unfrequently combine together in producing the same results; but there is no doubt that they may produce essentially the same results separately; and they have their distinct laws

of action. Hence the necessity of treating of them under distinct heads.

§ 67. Of the original Causes of inordinately excited Conceptions.

It becomes here an interesting inquiry, upon what causes disordered conceptions depend? One of the causes of them is probably to be found, in the first place, in the mind itself; that is to say, in some other part of the mind disconnected from the conceptions themselves. A disordered state of the propensities and passions may, for instance, produce a disordered state of the conceptions. Take an individual who is of a very sanguine temperament (in whom that state of mind which is denominated Hope is predominant), and it will be found, I suppose, that his conceptions of those prospective objects at which he aims are much more distinct and vivid than those of another person in whom hope is deficient. We do not undertake to explain how the vividness of one state of mind communicates itself, as in this case, to another; but there will probably be no diversity of opinion as to the fact.

Take, again, an individual in whom the passion of fear exists in an inordinate degree. It is notorious that such a person will magnify difficulties and dangers. His agitated mind will give outline, and prominence, and distinctness to objects which scarcely attract the notice of another person. So intense are his conceptions, that his belief is, in a great degree, controlled by them; and, against the remon

strances of his reason, he peoples the darkness, and even the day itself, with imaginary conspirators against his person, and with thieves that lay in wait for his property.

(II.) And why may we not suppose, furthermore, that the conceptive faculty itself, independently of its connexion with the other mental powers, may sometimes be disordered? The mind has its nature and its laws; and, although it cannot be diseased or disordered in the same way that a material existence may be, yet sound philosophy does not forbid the supposition that it may possibly be susceptible of derangement in such way and degree as may be consistent with its own nature. Take, for instance, the susceptibility of Belief. The state of mind which we call belief has its laws, and may be regarded as a universal attribute of the mental nature. In other words, all men have this susceptibility. Furthermore, in the great mass of mankind it exists nearly in the same degree, and exhibits the same manifestations. And yet it is well known that in some individuals it discovers an extreme quickness, an astonishing facility; so much so, that the persons in whom this peculiarity exists unhesitatingly receive every statement which is made to them, however improbable and contradictory. The susceptibility obviously exists in an unnatural and disordered state, which in its action results in annulling the beneficial tendencies of the other parts of the mind, and renders the person, besides making him a common laughing-stock, useless, in a great degree, to society. This is, beyond all question, to be considered

as a disordered state of the mind; but the disorder does not appear to result from the unnatural and disordered position and influence of other parts of the mind, nor from anything peculiar, so far as we can perceive, in the sensorial organization. The violation of nature is to be found in the mental trait itself. The disease (if we may be allowed to apply the term to mental existences) is connatural, not in the body, but the mind itself, and in that particular part of the mind.

We introduce this statement, it will be noticed, in illustration of the general doctrine that a disorder of the mind may be connatural; that is to say, may really have its foundation in the constitution and facts of the mental, in distinction from the physical nature. And if the susceptibility of belief or any other mental attribute may be disordered in itself, why may not the conceptive power be disordered in itself also? We suppose it, at least, to be possible.

68. Instance Illustrative of this Subject.

We bring the remarks of this chapter to a close by introducing an instance where the Conceptive power seems to have been inordinately excited; and where, also, the results appear to have been more marked than they would otherwise have been, in consequence of the sympathetic influence of the very vivid conceptions on the disordered physical system. “In March, 1829" (says Dr. Macnish, in his Philosophy of Sleep, chap. xv.), "during an attack of fever, accompanied with violent action in the brain, I experienced illusions of a very peculiar kind.