E2P18S
Scholium — Part II
Latin
Hinc clare intelligimus quid sit memoria. Est enim nihil aliud quam quædam concatenatio idearum naturam rerum quæ extra corpus humanum sunt involventium quæ in mente fit secundum ordinem et concatenationem affectionum corporis humani. Dico primo concatenationem esse illarum tantum idearum quæ naturam rerum quæ extra corpus humanum sunt, involvunt, non autem idearum quæ earundem rerum naturam explicant. Sunt enim revera (per propositionem 16 hujus) ideæ affectionum corporis humani quæ tam hujus quam corporum externorum naturam involvunt. Dico secundo hanc concatenationem fieri secundum ordinem et concatenationem affectionum corporis humani ut ipsam distinguerem a concatenatione idearum quæ fit secundum ordinem intellectus quo res per primas suas causas mens percipit et qui in omnibus hominibus idem est. Atque hinc porro clare intelligimus cur mens ex cogitatione unius rei statim in alterius rei cogitationem incidat quæ nullam cum priore habet similitudinem; ut exempli gratia ex cogitatione vocis pomi homo romanus statim in cogitationem fructus incidet qui nullam cum articulato illo sono habet similitudinem nec aliquid commune nisi quod ejusdem hominis corpus ab his duobus affectum sæpe fuit hoc est quod ipse homo sæpe vocem pomum audivit dum ipsum fructum videret et sic unusquisque ex una in aliam cogitationem incidet prout rerum imagines uniuscujusque consuetudo in corpore ordinavit. Nam miles exempli gratia visis in arena equi vestigiis statim ex cogitatione equi in cogitationem equitis et inde in cogitationem belli etc. incidet. At rusticus ex cogitatione equi in cogitationem aratri, agri etc. incidet et sic unusquisque prout rerum imagines consuevit hoc vel alio modo jungere et concatenare, ex una in hanc vel aliam incidet cogitationem.
English (Elwes 1883)
We now clearly see what Memory is. It is simply a certain association of ideas involving the nature of things outside the human body, which association arises in the mind according to the order and association of the modifications (affectiones) of the human body. I say, first, it is an association of those ideas only, which involve the nature of things outside the human body: not of ideas which answer to the nature of the said things: ideas of the modifications of the human body are, strictly speaking (II. xvi.), those which involve the nature both of the human body and of external bodies. I say, secondly, that this association arises according to the order and association of the modifications of the human body, in order to distinguish it from that association of ideas, which arises from the order of the intellect, whereby the mind perceives things through their primary causes, and which is in all men the same. And hence we can further clearly understand, why the mind from the thought of one thing, should straightway arrive at the thought of another thing, which has no similarity with the first; for instance, from the thought of the word pomum (an apple), a Roman would straightway arrive at the thought of the fruit apple, which has no similitude with the articulate sound in question, nor anything in common with it, except that the body of the man has often been affected by these two things; that is, that the man has often heard the word pomum, while he was looking at the fruit; similarly every man will go on from one thought to another, according as his habit has ordered the images of things in his body. For a soldier, for instance, when he sees the tracks of a horse in sand, will at once pass from the thought of a horse to the thought of a horseman, and thence to the thought of war, &c.; while a countryman will proceed from the thought of a horse to the thought of a plough, a field, &c. Thus every man will follow this or that train of thought, according as he has been in the habit of conjoining and associating the mental images of things in this or that manner.
Modern English
From this we clearly understand what memory is. It is simply a certain chain of ideas involving the nature of things outside the human body, which arises in the mind according to the order and chain of the affections of the human body. I say, first, that it is a chain of those ideas only that involve the nature of things outside the human body — not of ideas that express the nature of those things themselves. For the ideas of the affections of the human body (E2P16) strictly speaking involve the nature both of the human body and of external bodies.
I say, second, that this chain arises according to the order and chain of the affections of the human body, to distinguish it from the chain of ideas that arises according to the order of the intellect, by which the mind perceives things through their first causes, and which is the same in all human beings.
From this we also clearly understand why the mind passes from the thought of one thing immediately to the thought of another that has no resemblance to the first. A Roman, for example, on hearing the word "pomum," will immediately pass to the thought of the fruit, which has no resemblance to that spoken sound and nothing in common with it except that the man's body was often affected by both together, that is, the man often heard the word "pomum" while seeing the fruit itself.
Every person will pass from one thought to another in the way that habit has ordered the images of things in their body. A soldier who sees horse-tracks in sand will at once pass from the thought of a horse to the thought of a rider, and from there to the thought of war, and so on. A farmer will pass from the thought of a horse to the thought of a plow, a field, and so on. Each person follows this or that train of thought according to how they have been accustomed to join and chain the images of things together.