Letter 13: 1. I do not feel pleasure in writing of the subjects which I was wont to discuss; I am not at liberty to write of new themes. I see that the one would not suit you, and that for the other I have no leisure.

Augustine to his dear friend Nebridius -- greetings. 1. I take no pleasure in writing about the subjects I used to discuss, and I am not free to take up new themes. The old topics would not suit you now, and for the new ones I have no leisure. Since I left you, I have had neither the opportunity nor the time to pick up and turn over in my mind the questions we used to investigate together. The winter nights are long, certainly, and I do not spend them entirely asleep -- but when I do have free time, other subjects push themselves forward as more urgent. So what am I to do? Should I be like someone who cannot speak, or like someone who will not? Neither you nor I want that. Very well, then -- here is what the late hours of the night managed to draw out of me while I was pursuing the subject of this letter. 2. You will certainly remember the question that kept coming up between us, leaving us breathless and excited: whether there is some kind of body that permanently belongs to the soul -- what some call its "vehicle." Now, if this thing moves from place to place, it clearly cannot be grasped by pure intellect. And whatever cannot be grasped by the intellect cannot truly be understood. It is not entirely impossible, however, to form a reasonable opinion about something that lies beyond the intellect if it at least falls within the reach of the senses. But when something is beyond both intellect and sense perception, any speculation about it is too groundless and trivial to bother with. And the thing we are discussing is precisely of this nature -- if it even exists at all. So I ask you: why do we not finally set aside this unimportant question, and with prayer to God raise ourselves to the supreme serenity of the highest Nature? 3. Perhaps you will reply: even though bodies themselves cannot be perceived by the intellect, we can perceive many things about material objects through the intellect -- for example, we know that matter exists. Who would deny this, or claim we are dealing here with mere probability rather than truth? Matter itself may belong to the realm of sense perception, but the assertion that it exists is an intellectual truth -- it cannot be known any other way. So perhaps this unknown body attached to the soul, while not perceptible to our senses, might be perceptible to senses more powerful than ours; and the question of whether it exists might at least be answerable by our minds. 4. If that is what you intend to argue, let me point out that the mental activity we call understanding works in two ways: either the mind grasps something within itself directly -- as when we understand that the intellect itself exists -- or it grasps something prompted by the senses, as when we understand that matter exists. In the first kind, we understand through ourselves, by seeking instruction from God about what is within us. In the second, we understand by seeking instruction from God about what our body and senses have pointed us toward. If this is correct, then no one can discover by intellect alone whether this body you speak of exists -- only someone whose senses have given them some indication of it could do that. If there is any living creature whose senses provide such an indication, we at least can plainly see that we are not among them. So I consider my earlier conclusion confirmed: this question about the soul's "vehicle" is simply not our problem to solve. I wish you would think this over carefully and let me know where your reflections lead you.

Letter 13 (A.D. 389) To Nebridius Augustine Sends Greeting. 1. I do not feel pleasure in writing of the subjects which I was wont to discuss; I am not at liberty to write of new themes. I see that the one would not suit you, and that for the other I have no leisure. For, since I left you, neither opportunity nor leisure has been given me for taking up and revolving the things which we are accustomed to investigate together. The winter nights are indeed too long, and they are not entirely spent in sleep by me; but when I have leisure, other subjects [than those which we used to discuss] present themselves as having a prior claim on my consideration. What, then, am I to do? Am I to be to you as one dumb, who cannot speak, or as one silent, who will not speak? Neither of these things is desired, either by you or by me. Come, then, and bear what the end of the night succeeded in eliciting from me during the time in which it was devoted to following out the subject of this letter. 2. You cannot but remember that a question often agitated between us, and which kept us agitated, breathless, and excited, was one concerning a body or kind of body, which belongs perpetually to the soul, and which, as you recollect, is called by some its vehicle. It is manifest that this thing, if it moves from place to place, is not cognisable by the understanding. But whatever is not cognisable by the understanding cannot be understood. It is not, however, utterly impossible to form an opinion approximating to the truth concerning a thing which is outside the province of the intellect, if it lies within the province of the senses. But when a thing is beyond the province of the intellect and of the senses, the speculations to which it gives rise are too baseless and trifling; and the thing of which we treat now is of this nature, if indeed it exists. Why, then, I ask, do we not finally dismiss this unimportant question, and with prayer to God raise ourselves to the supreme serenity of the Highest existing nature? 3. Perhaps you may here reply: Although bodies cannot be perceived by the understanding, we can perceive with the understanding many things concerning material objects; e.g. we know that matter exists. For who will deny this, or affirm that in this we have to do with the probable rather than the true? Thus, though matter itself lies among things probable, it is a most indisputable truth that something like it exists in nature. Matter itself is therefore pronounced to be an object cognisable by the senses; but the assertion of its existence is pronounced to be a truth cognisable by the intellect, for it cannot be perceived otherwise. And so this unknown body, about which we inquire, upon which the soul depends for its power to move from place to place, may possibly be cognisable by senses more powerful than we possess, though not by ours; and at all events, the question whether it exists is one which may be solved by our understandings. 4. If you intend to say this, let me remind you that the mental act we call understanding is done by us in two ways: either by the mind and reason within itself, as when we understand that the intellect itself exists; or by occasion of suggestion from the senses, as in the case above mentioned, when we understand that matter exists. In the first of these two kinds of acts we understand through ourselves, i.e. by asking instruction of God concerning that which is within us; but in the second we understand by asking instruction of God regarding that of which intimation is given to us by the body and the senses. If these things be found true, no one can by his understanding discover whether that body of which you speak exists or not, but the person to whom his senses have given some intimation concerning it. If there be any living creature to which the senses give such intimation, since we at least see plainly that we are not among the number, I regard the conclusion established which I began to state a little ago, that the question [about the vehicle of the soul] is one which does not concern us. I wish you would consider this over and over again, and take care to let me know the product of your consideration.

EPISTOLA 13 Scripta eodem tempore (389-91). Quaestionem de animae quodam corpore subtiliore quam quod sensibus attingi possit declarat Augustinus nihil ad se pertinentem (n. 1-2) explanans quid intelligibile vel sensibile quidque mente vel sensu comprehendatur (n. 3-4).   Nebridio Augustinus Epistola noctu scripta. 1. Usitata tibi scribere non libet, nova non licet. Alterum enim video tibi non convenire, alterum non mihi vacare. Nam ex quo abii abs te, nulla mihi opportunitas, nullum otium datum est ea quae inter nos quaerere solemus, agitandi atque versandi. Sunt quidem hiemales nimis longae noctes, nec a me totae dormiuntur; sed se objiciunt magis cogitanda cum otium est, quae diffirmando sunt otio necessaria. Quid ergo faciam? mutusne apud te, an tacitus sim? Neutrum vis, neutrum volo. Quare age, atque accipe quod de me excudere potuit ultimum noctis, quamdiu exsequebatur, quo haec epistola scripta est. Illud animae quod dicitur "vehiculum". 2. Necesse est te meminisse quod crebro inter nos sermone iactatum est, nosque iactavit anhelantes, atque aestuantes, de animae scilicet vel perpetuo quodam corpore, vel quasi corpore, quod a nonnullis etiam dici vehiculum recordaris. Quam rem certe siquidem loco movetur, non esse intellegibilem, clarum est. Quidquid autem intellegibile non est, intellegi non potest. At quod intellectum fugit, si saltem sensum non refugit, aestimare inde aliquid verisimiliter non usquequaque denegatur. Quod vero neque intellegi neque sentiri potest, temerariam nimis atque nugatoriam gignit opinionem; et hoc de quod agimus tale est, si tamen est. Cur ergo, quaeso te, non nobis ad hanc quaestiunculam indicimus ferias, et nos totos imprecato Deo in summam serenitatem naturae summae viventis attollimus? De corpore sensibili deque intellegibili. 3. Hic forsitan dicas, quanquam corpora percipi nequeant, multa nos tamen ad corpus pertinentia intellegibiliter posse percipere, ut est quod novimus esse corpus. Quis enim neget, aut quis hoc verisimile potius quam verum esse fateatur? Ita cum ipsum corpus verisimile sit, esse tamen in natura tale quiddam verissimum est: ergo corpus sensibile, esse autem corpus intelligibile iudicatur; non enim posset aliter percipi. Ita nescio quid illud, de quo quaerimus, corpus, quo inniti anima, ut de loco ad locum transeat, putatur, quanquam etiamsi non sensibus nostris, tamen quibusdam longe vegetioribus sensibile sit, utrum tamen sit, intellegibiliter cognosci potest. De sensibili atque intellegibili cognitione. 4. Hoc si dices, veniat in mentem illud quod intellegere appellamus, duobus modis in nobis fieri: aut ipsa per se mente atque ratione intrinsecus, ut cum intellegimus esse ipsum intellectum; aut admonitione a sensibus, ut id quod iam dictum est, cum intelligimus esse corpus. In quibus duobus generibus illud primum per nos, id est, de eo quod apud nos est Deum consulendo; hoc autem secundum de eo quod a corpore sensuque nuntiatur, nihilominus Deum consulendo intellegimus. Quae si rata sunt, nemo de illo corpore utrum sit intellegere potest, nisi cui sensus quidquam de illo nuntiarit. In quo animantium numero si ullus est, nos quoniam non esse perspicimus, illud etiam perfectum puto, quod supra dicere coeperam, non ad nos istam pertinere quaestionem. Haec etiam atque etiam cogites velim, et quod cogitando generis, ut noverim cures.