But another period was soon to follow, a period in which ages of long and dreary ignorance were to be followed by ages of futile labour, as long and dreary. No beautiful moral speculations were then to compensate the poverty of intellectual science. But morality, and even religion itself, were to be degraded, as little more than technical terms of a cold and unmeaning logic. The knowledge of our mental frame was then, indeed, professedly cultivated with most assiduous zeal; and if much technical phraseology, and much contention, were sufficient to constitute an elaborate science, that assiduous zeal might well deserve to have been rewarded with so honourable a name. But what reasonable hope of a progress truly scientific could be formed, when to treat of the philosophy of mind was to treat of every thing but of the mind and its affections; when some of the most important questions, with respect to it, were, Whether its essence were distinct from its existence? whether its essence therefore might subsist, when it had no actual existence? and what were all the qualities inherent in it as a nonentity? In morals, whether ethics were an art or a science? whether, if the mind had freedom of choice, this independent will be an entity or a quiddity? and whether we should say, with a dozen schoolmen, that virtue is good, because it has intrinsic goodness, or, with a dozen more, that it has this intrinsic goodness, because it is good?
In natural theology, questions of equal moment were contested with equal keenness and subtilty; but they related less to the Deity, of whose nature, transcendent as it is, the whole universe may be considered as in some degree a faint revelation, than to those spiritual ministers of his power, of whose very existence nature affords no evidence, and of whom revelation itself may be said to teach us little but the mere existence. Whether angels pass from one point of space to another, without passing through the intermediate points? whether they can visually discern objects in the dark? whether more than one can exist at the same moment in the same physical point? whether they can exist in a perfect vacuum, with any relation to the absolute incorporeal void? and whether if an angel were in vacuo, the void could still truly be termed perfect?—such, or similar to these were the great inquiries in that department of Natural Theology, to which, as to a separate science, was given the name of Angelography: and of the same kind were the principal inquiries with respect to the Deity himself, not so much an examination of the evidence which nature affords of his self-existence, and power, and wisdom, and goodness, those sublime qualities which even our weakness cannot contemplate without deriving some additional dignity from the very greatness which it adores, as a solution of more subtile points, whether he exist in imaginary space as much as in the space that is real? whether he can cause a mode to exist without a substance? whether, in knowing all things, he know universals, or only things singular? and whether he love a possible unexisting angel better than an actually existing insect?
“Indignandum de isto, non disputandum est.”—“Sed non debuit hoc nobis esse propositum arguta disserere,[1] et philosophiam in has augustias ex sua majestate detrahere. Quanto satius est, ire aperta via et recta, quam sibi ipsi flexus disponere, quos cum magna molestia debeas relegere?”[2]—“Why waste ourselves,” says the same eloquent moralist; “why torture and waste ourselves in questions, which there is more real subtilty in despising than in solving?”—
“Quid te troques et maceras, in ea quæstione quam subtilius est contempsisse quam solvere?”[3]
From the necessity of such inquiries we are now fortunately freed. The frivolous solemnities of argument, which, in the disputations of Scotists and Thomists, and the long controversy of the believers and rejectors of the universal a parti rei, rendered human ignorance so very proud of its temporary triumphs over human ignorance, at length are hushed forever; and, so precarious is all that glory, of which men are the dispensers, that the most subtile works, which for ages conferred on their authors a reverence more than praise, and almost worship, would now scarcely find a philosophic adventurer, so bold, as to avow them for his own.
The progress of intellectual philosophy may indeed, as yet, have been less considerable than was to be hoped under its present better auspices. But it is not a little, to have escaped from a labyrinth, so very intricate, and so very dark, even though we should have done nothing more than advance into sunshine and an open path, with a long journey of discovery still before us. We have at last arrived at the important truth, which now seems so very obvious a one, that the mind is to be known best by observation of the series of changes which it presents, and of all the circumstances which precede and follow these; that, in attempting to explain its phenomena, therefore, we should know what those phenomena are; and that we might as well attempt to discover, by logic, unaided by observation or experiment, the various coloured rays that enter into the composition of a sunbeam, as to discover, by dialectic subtilties, a priori, the various feelings that enter into the composition of a single thought or passion.
The mind, it is evident, may, like the body to which it is united, or the material objects which surround it, be considered simply as a substance possessing certain qualities, susceptible of various affections or modifications, which, existing successively as momentary states of the mind, constitute all the phenomena of thought and feeling. The general circumstances in which these changes of state succeed each other, or, in other words, the laws of their succession, may be pointed out, and the phenomena arranged in various classes, according as they may resemble each other, in the circumstances that precede or follow them, or in other circumstances of obvious analogy. There is, in short, a science that may be termed mental physiology, as there is another science relating to the structure and offices of our corporeal frame, to which the term physiology is more commonly applied; and as, by observation and experiment, we endeavour to trace those series of changes which are constantly taking place in our material part, from the first moment of animation to the moment of death; so, by observation, and in some measure also by experiment, we endeavour to trace the series of changes that take place in the mind, fugitive as these successions are, and rendered doubly perplexing by the reciprocal combinations into which they flow. The innumerable changes, corporeal and mental, we reduce, by generalizing, to a few classes; and we speak, in reference to the mind, of its faculties or functions of perception, memory, reason, as we speak, in reference to the body, of its functions of respiration, circulation, nutrition. This mental physiology, in which the mind is considered simply as a substance endowed with certain susceptibilities, and variously affected or modified in consequence, will demand of course our first inquiry; and I trust that the intellectual analyses, into which we shall be led by it, will afford results that will repay the labour of persevering attention, which they may often require from you.
In one very important respect, however, the inquiries, relating to the physiology of mind, differ from those which relate to the physiology of our animal frame. If we could render ourselves acquainted with the intimate structure of our bodily organs, and all the changes which take place, in the exercise of their various functions, our labour, with respect to them, might be said to terminate. But though our intellectual analysis were perfect, so that we could distinguish, in our most complex thought or emotion, its constituent elements, and trace with exactness the series of simpler thoughts which have progressively given rise to them, other inquiries, equally, or still more important, would remain. We do not know all which is to be known of the mind, when we know all its phenomena, as we know all which can be known of matter, when we know the appearances which it presents, in every situation in which it is possible to place it, and the manner in which it then acts or is acted upon by other bodies. When we know that man has certain affections and passions, there still remains the great inquiry, as to the propriety or impropriety of those passions, and of the conduct to which they lead. We have to consider, not merely how he is capable of acting, but also, whether, acting in the manner supposed, he would be fulfilling a duty or perpetrating a crime. Every enjoyment which man can confer on man, and every evil, which he can reciprocally inflict or suffer, thus become objects of two sciences—first of that intellectual analysis which traces the happiness and misery, in their various forms and sequence, as mere phenomena or states of the substance mind;—and secondly, of that ethereal judgment, which measures our approbation and disapprobation, estimating, with more than judicial scrutiny, not merely what is done, but what is scarcely thought in secrecy and silence, and discriminating some element of moral good or evil, in all the physical good and evil, which it is in our feeble power to execute, or in our still frailer heart, to conceive and desire.
To this second department of inquiry belong the doctrines of general ethics.