Propositions 15 to 24

15. Anything can, accidentally, be the cause of pleasure, pain, or desire.

Proof: The mind is simultaneously affected by 2 emotions.

1. One neither increases nor diminishes its power of activity
2. The other either increases or reduces the said power (3. Post. 1).

From 3.14 follows that whenever the mind is afterwards affected by the former, through its true cause, which (by hypothesis) neither increases nor diminishes its power of action, it will be at the same time affected by the latter, which does increase or diminish its power of activity.

• The mind that is (3.11. note) it will be affected with pleasure or pain.

Thus the former of the two emotions will, not through itself, but accidentally, be the cause of pleasure or pain.

In the same way also it can be easily shown, that a thing may be accidentally the cause of desire. Q.E.D.

Corollary: Simply from the fact that we have regarded a thing with the emotion of pleasure or pain, though that thing be not the efficient cause of the emotion, we can either love or hate it.

Proof: For from this fact alone it arises (3.14), that the mind afterwards conceiving the said thing is affected with the emotion of pleasure or pain, that is (3.11 note), according as the power of the mind and body may be increased or diminished, etc.

Consequently (3.12), according as the mind may desire or shrink from the conception of it (3.13 Coroll.), in other words (3.13. note), according as it may love or hate the same. Q.E.D.

Note: Hence we understand how we can love or hate a thing without any cause for our emotion being known to us, merely from sympathy or antipathy.

We should refer to the same category those objects, which affect us pleasurably or painfully, simply because they resemble other objects which affect us in the same way.

I will show this in the next Proposition.

I know that certain authors who first introduced the terms “sympathy” and “antipathy,” wished to signify some occult qualities in things.

Nevertheless, I think we can use those terms to indicate known or manifest qualities.

16. Simply from the fact that we conceive, that a given object has some point of resemblance with another object which is used to affect the mind pleasurably or painfully, although the point of resemblance be not the efficient cause of the said emotions, we shall still regard the first-named object with love or hate.

Proof: The point of resemblance was in the object (by hypothesis), when we regarded it with pleasure or pain, thus (3.14), when the mind is affected by the image thereof, it will straightway be affected by one or the other emotion, and consequently the thing, which we perceive to have the same point of resemblance, will be accidentally (3.15) a cause of pleasure or pain.

Thus (by the foregoing Corollary), although the point in which the two objects resemble one another be not the efficient cause of the emotion, we shall still regard the first-named object with love or hate. Q.E.D.

17. If we conceive that a thing, which is wont to affect us painfully, has any point of resemblance with another thing which is wont to affect us with an equally strong emotion of pleasure, we shall hate the first-named thing, and at the same time we shall love it.

Proof: The given thing is (by hypothesis) in itself a cause of pain, and (3.13. note), in so far as we imagine it with this emotion, we shall hate it=

Further, inasmuch as we conceive that it has some point of resemblance to something else, which is wont to affect us with an equally strong emotion of pleasure, we shall with an equally strong impulse of pleasure love it (3.16).

Thus we shall both hate and love the same thing. Q.E.D.

Note: This disposition of the mind, which arises from two contrary emotions, is called vacillation; it stands to the emotions in the same relation as doubt does to the imagination (2.44. note).

Vacillation and doubt do not differ from each other, except as greater differs from less.

But we must bear in mind that I have deduced this vacillation from causes, which give rise through themselves to one of the emotions, and to the other accidentally.

I have done this so that they might be more easily deduced from what went before.

But I do not deny that vacillation of the disposition generally arises from an object, which is the efficient cause of both emotions.

The human body is composed (2. Post. 1) of a variety of individual parts of different nature, and may therefore (Ax. 1 after Lemma 3 after 2.13.) be affected in a variety of different ways by one and the same body.

On the contrary, as one and the same thing can be affected in many ways, it can also in many different ways affect one and the same part of the body. Hence we can easily conceive, that one and the same object may be the cause of many and conflicting emotions.

18. A man is as much affected pleasurably or painfully by the image of a thing past or future as by the image of a thing present.

Proof: So long as a man is affected by the image of anything, he will regard that thing as present, even though it be non—existent (2.17. and Coroll.), he will not conceive it as past or future, except in so far as its image is joined to the image of time past or future (2.44. note).

Wherefore the image of a thing, regarded in itself alone, is identical, whether it be referred to time past, time future, or time present.

That is (2.16. Coroll.), the disposition or emotion of the body is identical, whether the image be of a thing past, future, or present.

Thus the emotion of pleasure or pain is the same, whether the image be of a thing past or future. Q.E.D.

Note 1: I call a thing past or future, as we either have been or shall be affected by it.

For instance, according as:

• we have seen it,
• we are about to see it,
• it has recreated us,
• it will recreate us,
• it has harmed us, or
• it will harm us.

We affirm a thing’s existence as we thus conceive it.

That is, the body is affected by no emotion which excludes the thing’s existence.

Therefore (2.17.) the body is affected by the thing’s image in the same way as if the thing were actually present.

However, those who have had many experiences generally vacillate when they regard a thing as future or past, and are usually in doubt about its issue (2.44 note). It follows that the emotions arising from similar images of things are not so constant, but are generally disturbed by the images of other things, until people become assured of the issue.

Note 2: We can thus understand what is meant by the terms Hope, Fear, Confidence, Despair, Joy, and Disappointment.[5]

Hope is just an inconstant pleasure, arising from the image of something future or past, of which we do not yet know the issue.

On the other hand, fear is an inconstant pain also arising from the image of something which we are in doubt of.

If the element of doubt is removed from these emotions, hope becomes Confidence and fear becomes Despair.

In other words, Pleasure or Pain arising from the image of something concerning which we have hoped or feared.

Joy is Pleasure arising from the image of something past of which we have doubted the issue.

Disappointment is the Pain opposed to Joy.

[5] Conscientiæ morsus—thus rendered by Mr. Pollock.

19. He who conceives that the object of his love is destroyed will feel pain.

If he conceives that it is preserved he will feel pleasure.

Proof: As far as possible, the mind endeavours to conceive those things which increase or help the body’s power of activity (3.12.).

In other words (3.12. note), those things which it loves.

But conception is helped by those things which postulate the existence of a thing, and contrariwise is hindered by those which exclude the existence of a thing (2.17).

Therefore the images of things, which postulate the existence of an object of love, help the mind’s endeavour to conceive the object of love, in other words (3.11. note), affect the mind pleasurably.

On the contrary, those things which exclude the existence of an object of love, hinder the aforesaid mental endeavour.

In other words, affect the mind painfully.

He, therefore, who conceives that the object of his love is destroyed will feel pain, etc. Q.E.D.

20. He who conceives that the object of his hate is destroyed will also feel pleasure.

Proof: The mind (3.13.) endeavours to conceive those things, which exclude the existence of things whereby the body’s power of activity is diminished or constrained; that is (.13. note).

It endeavours to conceive such things as exclude the existence of what it hates.

Therefore the image of a thing, which excludes the existence of what the mind hates, helps the aforesaid mental effort.

In other words (3.11. note), affects the mind pleasurably.

Thus, he who conceives that the object of his hate is destroyed will feel pleasure. Q.E.D.

21. He who conceives, that the object of his love is affected pleasurably or painfully, will himself be affected pleasurably or painfully.

The one or the other emotion will be greater or less in the lover according as it is greater or less in the thing loved.

Proof: The images of things (as we showed in 3.19) which postulate the existence of the object of love, help the mind’s endeavour to conceive the said object.

But pleasure postulates the existence of something feeling pleasure, so much the more in proportion as the emotion of pleasure is greater; for it is (3.11. note) a transition to a greater perfection.

Therefore, the image of pleasure in the object of love helps the mental endeavour of the lover.

That is, it affects the lover pleasurably, and so much the more, in proportion as this emotion may have been greater in the object of love.

This was our first point.

Further, in so far as a thing is affected with pain, it is to that extent destroyed, the extent being in proportion to the amount of pain (3.11. note).

Therefore (3.19.) he who conceives, that the object of his love is affected painfully, will himself be affected painfully, in proportion as the said emotion is greater or less in the object of love. Q.E.D.

22. If we conceive that anything pleasurably affects some object of our love, we shall be affected with love towards that thing.

Contrariwise, if we conceive that it affects an object of our love painfully, we shall be affected with hatred towards it.

Proof: He, who affects pleasurably or painfully the object of our love, affects us also pleasurably or painfully—that is, if we conceive the loved object as affected with the said pleasure or pain (3.21).

But this pleasure or pain is postulated to come to us accompanied by the idea of an external cause; therefore (III. xiii. note), if we conceive that anyone affects an object of our love pleasurably or painfully, we shall be affected with love or hatred towards him. Q.E.D.

Note: Prop. 21 explains to us the nature of Pity, which we may define as pain arising from another’s hurt.

What term we can use for pleasure arising from another’s gain, I know not.

We will call the love towards him who confers a benefit on another, Approval;

The hatred towards him who injures another, we will call Indignation.

We must further remark, that we not only feel pity for a thing which we have loved (as shown in 3. 21), but also for a thing which we have hitherto regarded without emotion, provided that we deem that it resembles ourselves (as I will show presently).

Thus, we bestow approval on one who has benefited anything resembling ourselves.

Contrariwise, are indignant with him who has done it an injury.

23. He who conceives, that an object of his hatred is painfully affected, will feel pleasure.

Contrariwise, if he thinks that the said object is pleasurably affected, he will feel pain.

Each of these emotions will be greater or less, according as its contrary is greater or less in the object of hatred.

Proof: In so far as an object of hatred is painfully affected, it is destroyed, to an extent proportioned to the strength of the pain (3.11. note).

Therefore, he (3.20.) who conceives, that some object of his hatred is painfully affected, will feel pleasure, to an extent proportioned to the amount of pain he conceives in the object of his hatred.

This was our first point. Again, pleasure postulates the existence of the pleasurably affected thing (3.11. note), in proportion as the pleasure is greater or less.

If anyone imagines that an object of his hatred is pleasurably affected, this conception (3.13.) will hinder his own endeavour to persist; in other words (3.11. note), he who hates will be painfully affected. Q.E.D.

Note: This pleasure can scarcely be felt unalloyed, and without any mental conflict.

For (as I am about to show in Prop. 27.), in so far as a man conceives that something similar to himself is affected by pain, he will himself be affected in like manner; and he will have the contrary emotion in contrary circumstances.

But here we are regarding hatred only.

24. If we conceive that anyone pleasurably affects an object of our hate, we shall feel hatred towards him also. If we conceive that he painfully affects that said object, we shall feel love towards him.

Proof: This proposition is proved in the same way as III. xxii., which see. Note= These and similar emotions of hatred are attributable to envy, which, accordingly, is nothing else but hatred, in so far as it is regarded as disposing a man to rejoice in another’s hurt, and to grieve at another’s advantage.