This observation will explain several phaenomena of the brute nature; from which fome have rafhly concluded, that they have the use of intellect and reafon as well as we. Thus, a horse, by travelling the fame road twice or thrice, learns to know it often better than his rider; from whence one might conclude, that he had fome idea of a road. But the fact truly is, that although, no doubt, the perception of this particular road is impreffed on his memory or imagination, and retained there, yet he has no idea of a road; because, not having that active self-moving power above-mentioned, his remembrance is only excited by the object being prefented again to his sense. At any other time, so far as we can discover, he never thinks of that road, nor is conscious that he has any fuch perception in his memory: And therefore it is impoffible that ever he can form the idea of a road, according to the process above described. Again, a horfe or a dog remembers his home, or the place where he is fed, and protected from the weather; but, fo far as we know, never thinks of that place, except when he is prompted by hunger, cold, love of fociety, or any other natu

ral appetite. And it is the fame with respect to the operations of the mind of the brute, as with respect to his perceptions of external objects: For not having that self-moving power which we have, he cannot review his own operations, of which he is not confcious; and therefore it is evident that he cannot form ideas of reflection.

any

From what is here faid, the difference betwixt perceptions of fenfe and ideas must appear manifold. In the first place, Those perceptions are only the materials from which ideas are formed; and therefore are as diftinct from ideas as the matter of thing is from its form. 2do, Perceptions of fense arise only from objects prefent; whereas ideas may be formed, and are commonly formed, from past fenfations, preserved in the memory or imagination. 3tio, The perceptions of fense preserved in the memory or imagination, are no more than the images of objects, fuch as they were prefented to the mind by the fenfes: But neither fense, memory, nor imagination, makes that comparison which we have fhewn to be abfolutely neceffary in order to form ideas. And hence it is, 4to, That the perceptions

of fenfe, though retained in the memory, are all of individual things; whereas ideas are all of generals, being of things common to many individuals. And, laftly, In the formation of ideas, the mind is altogether active; whereas, in the perceptions of sense, it is merely paffive. What confufion, therefore, muft it not have produced in philofophy, the not distinguishing things fo different in their nature, and the operations of faculties fo different as fenfe and intellect?— And fo much for the ideas that are formed immediately from the perceptions of sense.

As to the ideas which arife from the operations of the mind, and which I fhall call, with Mr Locke, ideas of reflection, they are formed in the fame manner: For the mind preferving the memory of its own operations, as well as of external objects, and reviewing and comparing together the individual operations thus preferved in the memory, and discovering fomething common to several of them, of that one common thing it forms the idea; and in that way we come by the ideas of doubting, deliberating, affirming, and of thinking in general. This, I believe, is agreeable to Mr Locke's notion of

fuch ideas; and, as he has obferved, under the operations of the mind we ought to include the passion as well as the action of the mind: So that the ideas of pleasure and pain, (not the actual feeling, for that is mere fenfation *), and of all their various modifications in the different paffions, are all ideas which we get from reflection. But we should carefully distinguish two things that he has not distinguished, viz. the particular operations of the mind, and the idea or general notion thence formed; which he has

* I call it mere fenfation, when there is no perception of any external object: For it is to be observed, that the word fenfation, as it is commonly used, is equivocal, denoting either the perception of any external object by the fenfes, or the inward feeling of pleasure or pain arifing from the body; and which is always accompanied with a certain emotion and alteration of the mind. This laft kind of fenfation is often joined with the former; for often, when we feel pain, we perceive at the fame time the external object that produces it; as when a man is pricked by a fword, or burnt with a hot iron. At other times, we feel pain without the perception of any external object; which is the cafe where the body labours under any disease. And as thus we have fenfation of pain, without the perception of any external object; fo, on the other hand, we have very frequently, and indeed moft commonly, the perception of external objects without either pain or pleasure.

confounded in the fame manner as he has confounded the particular perceptions of fenfe with the ideas formed from them.

From this account of the formation of our ideas, it is evident, that the mind forms them without any affiftance from the fenfes. With refpect to the ideas of reflection, there cannot be the least doubt, as the fenfes do not fo much as furnish the materials out of which they are formed: And, with respect to the ideas arising from sensation, it is evident, that the fenfe furnishes only the materials, upon which the mind works by itself, and forms the ideas: For those ideas, as we have fhewn, arife from the mind's comparing together the perceptions of fenfe, and discovering betwixt them certain refemblances and fimilitudes. Now, it is impoffible that the sense can compare or perceive relations of any kind; and therefore this comparing faculty is the peculiar property of the rational, or, as the Greeks call it, the logical mind: For the Greek word Ayes, which the Latins render by the term ratio, properly fignifies a relation. And accordingly Euclid, who must be supposed to

* The definition is, Λόγος ἐστι μεγεθων ομογενων καλα της Xixotala moia cxecis, lib. 5. def. 3. And the learned in the VOL. I. F