Lastly. "It may be observed," says Dr. Reid, "that, in this doctrine, not only is consciousness confounded with memory, but which is still more strange, personal identity is confounded with the evidence which we have of personal identity." Here again the Dr. maintains a doctrine altogether incompatible with his own system.

He maintains, that by consciousness we could not obtain even the idea of personal identity, since by that act of the mind we can arrive at a knowledge only of what is immediately present in it; how then can it be the evidence of personal identity? He should have said, conformably to his own theory, that memory is the evidence of personal identity. This, indeed, would not be true, if by the expression memory or consciousness is the evidence of our personal identity, he meant to exclude every other species of evidence. I may be convinced by the testimony of credible witnesses, or by other circumstances, that I was the person who performed a certain act, although my memory does not retain it, or it took place at a period of life lost to me in utter oblivion, on account of my early age, or a fit of illness. In the Arabian Night's Entertainments, we are told that the Caliph, Haroun- Alraschid, once upon a time, while taking his periodical tour at night, through the city of Bagdat in disguise, fell in company with a citizen of singular humour, by the name of Abou-Hassan, who took him to his house and sumptuously entertained him. During the course of conversation, Abou Hassan, not knowing that his guest was the commander of the faithful, expressed the great satisfaction it would afford him for a short time, to exercise the authority of the Caliph. From that moment, Haroun- Alraschid, determined to amuse himself, by giving the citizen an opportunity of tasting what he supposed to be the sweets of arbitrary power. By his order, Abou-Hassan is taken during sleep, and transported while unconscious of it, to the palace, and placed in the royal bed. Directions are given,

that the same attendance and homage shall be paid him, as it is customary to bestow upon the real Caliph. Every possible preparation is made to convince him that he is such.

Upon waking in the morning, what is the astonishment of Abou-Hassan, to find himself thus laid under a canopy of state, surrounded with the splendour of royalty, with a magnificent retinue of servants and courtiers subject to his will, and sedulously anticipating his wishes; served with the most costly dishes, obsequiously attended by all the greatest men of his nation; and, at length summoned to the tribunal, from which he is to distribute justice to the submissive crowd. For a long time he cannot bring himself to believe that he is not dreaming, and that all he perceives is not a delusion of the senses. His doubts, however, are gradually dissipated by what he now perceives to be real facts, and he at length is brought to believe himself the true and genuine Caliph. In this story we find some admirable touches of nature, as is usual in that wild and grotesque performance, interspersed with improbable fictions. The memory and consciousness of Abou-Hassan united, would seem to make it certain, that he is only an obscure individual; but the testimony of those around him, and the real scenes continually presented to his view, afford an evidence which soon preponderates over that of his memory, and leads him to the conclusion, that he has been hitherto deluded with deceptive visions, and just now begins to behold things in their real state. In this eastern tale we see a faithful representation of nature, and Abou-Hassan might under such forms of government, readily find an antitype in real life. By violent attacks of illness, men are sometimes completely deprived of all memory of their past lives. Would it be impossible under such circumstances to convince them, that they are the same persons, who entered into certain engagements, or performed any previous acts of their lives?

BOOK III.-CHAPTER I.

On the Grounds of Human Knowledge.

THE doctrine of innate ideas having been refuted by Mr. Locke, and being now considered as exploded from philosophy, we have undertaken to show that all our simple ideas, are obtained through the inlets of sensation and reflection, as asserted by that metaphysician. We proceed to follow the progress of the human mind, in the acquisition of knowledge, and ascertain the foundations upon which it rests. Instead of the animated statue of Condillac, we will suppose a philosopher endowed with all the bodily and mental powers, bestowed upon our race by the Creator, and with a thirst for improvement, and a turn to scientific investigation, but entirely destitute of ideas, even of the original perceptions of sense, to set himself forth in the world in quest of information. By sensation or the power of perceiving, through the instrumentality of the five organs of sense, hearing, seeing, tasting, smell and touch, he derives intelligence of the external world, of all extended substances and their properties; and by reflection, he becomes acquainted with the internal world, or his own mind, and its properties and operations. From these two fountains flow all his knowledge, both of the physical and moral world. The senses internal and external, become our first instructors, and through their aid it is, that advancing from step to step, we gradually collect the lessons of experience, until at length after an ample accumulation of facts, by experience and observation, availing ourselves of the method of induction, we

establish the great maxim of truth, and principles of science. Experience, therefore, may be regarded as having its commencement in the notices, conveyed into the mind by sensation and reflection, and having its consummation in the great truths, to which we are able to attain by induction.

Before our philosopher has proceeded far in his examination of nature, he discovers that he is possessed of powers, that enable him to arrive at a new species of truth, not always depending upon experience, though posterior to it in the order of his attainments: namely, those truths which he discovers from tracing the connection of his ideas, or the immutable relations of things. These are called immutable and eternal truths, and properly constitute demonstration; such as those of mathematics, and some of those that come under the denomination of metaphysics, moral science, and natural religion. These all have their foundation, in what are denominated intuitive judgments, first principles or axiomatic truths, and lead us on frequently through the finest speculations of the human mind, to the most important and sublime conclusions.

Thirdly. Finding that there are many facts, at which it would be impossible for us to arrive, during the limited experience of any human being, we learn to open to ourselves a new source of information, in the testimony of other men.

Experience, intuition, and testimony, are justly regarded as the three grounds of human knowledge, and we shall proceed to treat of each of them distinctly, and illustrate in what part of our knowledge we are able to attain to absolute certainty, and where we must rest contented with probability.