“The other way of retention, is the power to revive again in our minds those ideas, which after imprinting have disappeared, or have been as it were laid aside out of sight; and thus we do, when we conceive heat or light, yellow or sweet, the object being removed. This is memory, which is, as it were the storehouse of our ideas. For the narrow mind of man not being capable of having many ideas under view and consideration at once, it was necessary to have a repository to lay up those ideas, which at another time it might have use of. But our ideas being nothing but actual perceptions in the mind, which cease to be any thing, when there is no perception of them, this laying up of our ideas in the repository of the memory, signifies no more but this, that the mind has a power in many cases to revive perceptions, which it has once had, with this additional perception annexed to them, that it has had them before. And in this sense it is, that our ideas are said to be in our memories, when indeed they are actually no where, but only there is an ability in the mind when it will to revive them again, and as it were paint them a-new on itself, though some with more, some with less difficulty; some more lively, and others more obscurely.”[97]
The doctrine of this truly eminent philosopher, therefore, is, that the presence of the external object, and the consequent organic change, are followed by an idea, “which is nothing but the actual perception;” and that the laying up of these ideas in the memory, signifies nothing more, than that the mind has, in many cases, a power to revive perceptions which it has once had. All this, I conceive, is the very doctrine of Dr Reid on the subject; and to have confuted Mr Locke, therefore, if it had been possible for him, must have been a very unfortunate confutation, as it would have been also to have confuted as completely the very opinions on the subject, which he was disposed himself to maintain.
I may now proceed further back, to another philosopher of great eminence, whose name, unfortunately for its reputation, is associated more with his political and religious errors, than with his analytical investigations of the nature of the phenomena of thought. The author to whom I allude is Hobbes, without all question one of the most acute intellectual inquirers of the country and age in which he lived. As the physiology of the mind, in Britain at least seemed at that time to be almost a new science, he was very generally complimented by his contemporary poets, as the discoverer of a new land. Some very beautiful Latin verses, addressed to him, I quoted to you, in a former Lecture, in which it was said, on occasion of his work on Human Nature, that the mind, which had before known all things, was now for the first time made known to itself.
“Omnia hactenus
Quæ nosse potuit, nota jam primum est sibi.”
And in which he was said, in revealing the mind, to have performed a work, next in divinity to that of creating it.
“Divinum est opus
Animum creare, proximum huic ostendere.”
By Cowley, who styles him “the discoverer of the golden lands of new philosophy,” he is compared to Columbus, with this difference, that the world, which that great navigator found, was left by him, rude and neglected, to the culture of future industry; while that which Hobbes discovered might be said to have been at once explored by him and civilized. The eloquence of his strong and perspicuous style, I may remark by the way, seems to have met with equal commendation, from his poetical panegyrists, with whom, certainly not from the excellence of his own verses, he appears to have been in singular favour. His style is thus described, in some verses of Sheffield, Duke of Buckingham: