E4P17S
Scholium — Part IV
Latin
His me causam ostendisse credo cur homines opinione magis quam vera ratione commoveantur et cur vera boni et mali cognitio animi commotiones excitet et sæpe omni libidinis generi cedat; unde illud poetæ natum : video meliora proboque, deteriora sequor. Quod idem etiam Ecclesiastes in mente habuisse videtur cum dixit : qui auget scientiam, auget dolorem. Atque hæc non eum in finem dico ut inde concludam præstabilius esse ignorare quam scire vel quod stulto intelligens in moderandis affectibus nihil intersit sed ideo quia necesse est nostræ naturæ tam potentiam quam impotentiam noscere ut determinare possimus quid ratio in moderandis affectibus possit et quid non possit et in hac parte de sola humana impotentia me acturum dixi. Nam de rationis in affectus potentia separatim agere constitui.
English (Elwes 1883)
I think I have now shown the reason, why men are moved by opinion more readily than by true reason, why it is that the true knowledge of good and evil stirs up conflicts in the soul, and often yields to every kind of passion. This state of things gave rise to the exclamation of the poet:[12]---- "The better path I gaze at and approve, The worse--I follow."
[12] Ov. Met. vii.20, "Video meliora proboque, Deteriora sequor."
Ecclesiastes seems to have had the same thought in his mind, when he says, "He who increaseth knowledge increaseth sorrow." I have not written the above with the object of drawing the conclusion, that ignorance is more excellent than knowledge, or that a wise man is on a par with a fool in controlling his emotions, but because it is necessary to know the power and the infirmity of our nature, before we can determine what reason can do in restraining the emotions, and what is beyond her power. I have said, that in the present part I shall merely treat of human infirmity. The power of reason over the emotions I have settled to treat separately.
Modern English
I believe I have now shown the reason why humans are moved more by opinion than by true reason, and why true knowledge of good and bad stirs up conflict in the mind and often yields to every kind of passion. This gives rise to the poet's words: I see the better course and approve it; the worse I follow. Ecclesiastes seems to have had the same thought when he wrote: he who increases knowledge increases sorrow. I say this not to conclude that ignorance is preferable to knowledge, or that there is no difference between a wise person and a fool in moderating the affects, but because it is necessary to know both the power and the powerlessness of our nature before we can determine what reason can and cannot do in moderating the affects. I said I would treat only of human powerlessness in this Part. The power of reason over the affects I have set aside for separate treatment.
With these few remarks I have explained the causes of human powerlessness and inconstancy, and why humans do not keep to the precepts of reason. It remains now to show what reason prescribes for us, which affects accord with the rules of human reason, and which are contrary to them. Before I begin to demonstrate these things in our extended geometrical order, I want to set out reason's dictates briefly first, so that they may be more readily grasped by everyone.
Since reason demands nothing contrary to nature, it demands that each person love themselves, seek what is truly useful to them — what is genuinely useful, that is — desire everything that truly leads them to greater perfection, and strive as far as they can to preserve their own being. This is as necessarily true as that the whole is greater than its part (E3P4).
Further, since virtue (E4D8) is nothing other than acting in accordance with the laws of one's own nature, and since no one strives to preserve their being except in accordance with those laws (E3P7), it follows first that the foundation of virtue is this very striving to preserve one's own being, and that happiness consists in the fact that a person is able to preserve their being. Second, it follows that virtue is to be desired for its own sake and that nothing more excellent or more useful to us exists for whose sake it ought to be desired. Third, it follows that those who take their own lives are powerless in mind and wholly overcome by external causes contrary to their nature.
Furthermore, from Postulate 4 of Part 2, it follows that we can never bring it about that we need nothing outside ourselves to preserve our being, and that we live in such a way as to have no dealings with things outside us. And if we consider our mind, our intellect would plainly be more imperfect if mind were alone and understood nothing besides itself. Many things outside us, therefore, exist that are useful to us and that are accordingly to be desired. None can be conceived more excellent than those that are entirely in accord with our nature. If, for example, two individuals of exactly the same nature unite, they form an individual twice as powerful as either alone.
Therefore, nothing is more useful to a human being than another human being. Nothing, I say, can be wished for more excellent for the preservation of their being than that all should so agree in all things that the minds and bodies of all should compose, as it were, one single mind and one single body, and that all should strive together, as far as they are able, to preserve their being, and all seek together what is useful to all in common. From this it follows that human beings governed by reason — that is, those who seek their own advantage under reason's guidance — desire nothing for themselves that they do not also desire for the rest of humanity, and are therefore just, trustworthy, and honourable.
These are the dictates of reason that I proposed to set out briefly here before beginning their longer demonstration. I did this so that, if possible, I might gain the attention of those who believe that this principle — that each person is bound to seek their own advantage — is the foundation of impiety rather than of virtue and piety. After briefly showing that the contrary is the case, I proceed to demonstrate it by the same method I have followed until now.