Benedict de Spinoza, THE ETHICS
(Ethica Ordine Geometrico Demonstrata)

Translated by R. H. M. Elwes





PART IV:  Of Human Bondage, or the Strength of the Emotions




PREFACE

Human infirmity in moderating and checking the emotions I name bondage: 
for, when a man is a prey to his emotions, he is not his own master, but 
lies at the mercy of fortune: so much so, that he is often compelled, 
while seeing that which is better for him, to follow that which is worse. 
Why this is so, and what is good or evil in the emotions, I propose to 
show in this part of my treatise. But, before I begin, it would be well 
to make a few prefatory observations on perfection and imperfection, 
good and evil. 

When a man has purposed to make a given thing, and has brought it 
to perfection, his work will be pronounced perfect, not only by 
himself, but by everyone who rightly knows, or thinks that he knows, 
the intention and aim of its author. For instance, suppose anyone sees a 
work (which I assume to be not yet completed), and knows that the aim 
of the author of that work is to build a house, he will call the work 
imperfect; he will, on the other hand, call it perfect, as soon as he 
sees that it is carried through to the end, which its author had purposed 
for it. But if a man sees a work, the like whereof he has never seen 
before, and if he knows not the intention of the artificer, he plainly 
cannot know, whether that work be perfect or imperfect. Such seems to 
be the primary meaning of these terms.

But, after men began to form general ideas, to think out types of 
houses, buildings, towers, &c., and to prefer certain types to others, 
it came about, that each man called perfect that which he saw agree 
with the general idea he had formed of the thing in question, and called 
imperfect that which he saw agree less with his own preconceived type, 
even though it had evidently been completed in accordance with the idea 
of its artificer.  This seems to be the only reason for calling natural 
phenomena, which, indeed, are not made with human hands, perfect or 
imperfect: for men are wont to form general ideas of things natural, no 
less than of things artificial, and such ideas they hold as types, 
believing that Nature (who they think does nothing without an object) 
has them in view, and has set them as types before herself. Therefore, 
when they behold something in Nature, which does not wholly conform to 
the preconceived type which they have formed of the thing in question, 
they say that Nature has fallen short or has blundered, and has left 
her work incomplete. Thus we see that men are wont to style natural 
phenomena perfect or imperfect rather from their own prejudices, than 
from true knowledge of what they pronounce upon.

Now we showed in the Appendix to Part I., that Nature does not work 
with an end in view. For the eternal and infinite Being, which we call 
God or Nature, acts by the same necessity as that whereby it exists. For 
we have shown, that by the same necessity of its nature, whereby it 
exists, it likewise works (I:xvi.). The reason or cause why God or Nature 
exists, and the reason why he acts, are one and the same.  Therefore, 
as he does not exist for the sake of an end, so neither does he act for 
the sake of an end; of his existence and of his action there is neither 
origin nor end. Wherefore, a cause which is called final is nothing else 
but human desire, in so far as it is considered as the origin or cause 
of anything. For example, when we say that to be inhabited is the final 
cause of this or that house, we mean nothing more than that a man, 
conceiving the conveniences of household life, had a desire to build a 
house. Wherefore, the being inhabited, in so far as it is regarded as 
a final cause, is nothing else but this particular desire, which is 
really the efficient cause; it is regarded as the primary cause, 
because men are generally ignorant of the causes of their desires. 
They are, as I have often said already, conscious of their own actions 
and appetites, but ignorant of the causes whereby they are determined 
to any particular desire. Therefore, the common saying that Nature 
sometimes falls short, or blunders, and produces things which are 
imperfect, I set down among the glosses treated of in the Appendix to 
Part 1.  Perfection and imperfection, then, are in reality merely modes 
of thinking, or notions which we form from a comparison among one 
another of individuals of the same species; hence I said above 
(II:Def.vi.), that by reality and perfection I mean the same thing. 
For we are wont to refer all the individual things in nature to one 
genus, which is called the highest genus, namely, to the category of 
Being, whereto absolutely all individuals in nature belong. Thus, in 
so far as we refer the individuals in nature to this category, and 
comparing them one with another, find that some possess more of being or 
reality than others, we, to this extent, say that some are more perfect 
than others. Again, in so far as we attribute to them anything implying 
negation - as term, end, infirmity, etc., we, to this extent, call them 
imperfect, because they do not affect our mind so much as the things 
which we call perfect, not because they have any intrinsic deficiency, 
or because Nature has blundered. For nothing lies within the scope of a 
thing's nature, save that which follows from the necessity of the nature 
of its efficient cause, and whatsoever follows from the necessity of the 
nature of its efficient cause necessarily comes to pass.

As for the terms good and bad, they indicate no positive quality in 
things regarded in themselves, but are merely modes of thinking, or 
notions which we form from the comparison of things one with another. 
Thus one and the same thing can be at the same time good, bad, and 
indifferent. For instance, music is good for him that is melancholy, 
bad for him that mourns; for him that is deaf, it is neither good nor 
bad.

Nevertheless, though this be so, the terms should still be retained. 
For, inasmuch as we desire to form an idea of man as a type of human 
nature which we may hold in view, it will be useful for us to retain 
the terms in question, in the sense I have indicated.

In what follows, then, I shall mean by, "good" that, which we 
certainly know to be a means of approaching more nearly to the type 
of human nature, which we have set before ourselves; by "bad," that 
which we certainly know to be a hindrance to us in approaching the 
said type.  Again, we shall that men are more perfect, or more imperfect, 
in proportion as they approach more or less nearly to the said type. 
For it must be specially remarked that, when I say that a man passes 
from a lesser to a greater perfection, or vice versa, I do not mean 
that he is changed from one essence or reality to another; for instance, 
a horse would be as completely destroyed by being changed into a man, 
as by being changed into an insect. What I mean is, that we conceive the 
thing's power of action, in so far as this is understood by its nature, 
to be increased or diminished. Lastly, by perfection in general I shall, 
as I have said, mean reality in other words, each thing's essence, in so 
far as it exists, and operates in a particular manner, and without paying 
any regard to its duration. For no given thing can be said to be more 
perfect, because it has passed a longer time in existence. The duration 
of things cannot be determined by their essence, for the essence of 
things involves no fixed and definite period of existence; but everything, 
whether it be more perfect or less perfect, will always be able to persist 
in existence with the same force wherewith it began to exist; wherefore, in 
this respect, all things are equal.



DEFINITIONS.

I. By good I mean that which we certainly know to be useful to us.

II. By evil I mean that which we certainly know to be a hindrance 
to us in the attainment of any good. (Concerning these terms see the 
foregoing preface towards the end.)

III. Particular things I call contingent in so far as, while regarding 
their essence only, we find nothing therein, which necessarily asserts 
their existence or excludes it.

IV. Particular things I call possible in so far as, while regarding the 
causes whereby they must be produced, we know not, whether such causes 
be determined for producing them.

(In I:xxxiii.note.i., I drew no distinction between possible and 
contingent, because there was in that place no need to distinguish 
them accurately.)

V. By conflicting emotions I mean those which draw a man in different 
directions, though they are of the same kind, such as luxury and 
avarice, which are both species of love, and are contraries, not 
by nature, but by accident.

VI. What I mean by emotion felt towards a thing, future, present, and 
past, I explained in III:xviii.,notes.i.,&ii., which see.

(But I should here also remark, that we can only distinctly conceive 
distance of space or time up to a certain definite limit; that is, all 
objects distant from us more than two hundred feet, or whose distance 
from the place where we are exceeds that which we can distinctly conceive, 
seem to be an equal distance from us, and all in the same plane; so also 
objects, whose time of existing is conceived as removed from the present 
by a longer interval than we can distinctly conceive, seem to be all 
equally distant from the present, and are set down, as it were, to the 
same moment of time.)

VII. By an end, for the sake of which we do something, I mean a desire.

VIII. By virtue (virtus) and power I mean the same thing; that is 
(III:vii.), virtue, in so far as it is referred to man, is a man's 
nature or essence, in so far as it has the power of effecting what 
can only be understood by the laws of that nature.



AXIOM.

There is no individual thing in nature, than which there is not 
another more powerful and strong. Whatsoever thing be given, there is 
something stronger whereby it can be destroyed.



PROPOSITIONS.
Prop. I. No positive quality possessed by a 
false idea is removed by the presence of 
what is true, in virtue of its being true.

Proof.- Falsity consists solely in the privation of knowledge which 
inadequate ideas involve (II:xxxv.), nor have they any positive 
quality on account of which they are called false (II:xxxiii.);   contrariwise, in so far as they
are referred to God, they are true 
(II:xxxii.).  Wherefore, if the positive quality possessed by a false 
idea were removed by the presence of what is true, in virtue of its 
being true, a true idea would then be removed by itself, which 
(IV:iii.) is absurd. Therefore, no positive quality possessed by a 
false idea, &c. Q.E.D.

Note.- This proposition is more clearly understood from II:xvi.Coroll.ii. 
For imagination is an idea, which indicates rather the present disposition 
of the human body than the nature of the external body; not indeed 
distinctly, but confusedly; whence it comes to pass, that the mind is 
said to err. For instance, when we look at the sun, we conceive that it 
is distant from us about two hundred feet; in this judgment we err, so 
long as we are in ignorance of its true distance; when its true distance 
is known, the error is removed, but not the imagination; or, in other 
words, the idea of the sun, which only explains tho nature of that 
luminary, in so far as the body is affected thereby: wherefore, though 
we know the real distance, we shall still nevertheless imagine the sun 
to be near us. For, as we said in III:xxxv.note, we do not imagine the sun 
to be so near us, because we are ignorant of its true distance, but because 
the mind conceives the magnitude of the sun to the extent that the body is 
affected thereby.  Thus, when the rays of the sun falling on the surface of 
water are reflected into our eyes, we imagine the sun as if it were in the 
water, though we are aware of its real position; and similarly other 
imaginations, wherein the mind is deceived whether they indicate the 
natural disposition of the body, or that its power of activity is 
increased or diminished, are not contrary to the truth, and do not vanish 
at its presence. It happens indeed that, when we mistakenly fear an evil, 
the fear vanishes when we hear the true tidings; but the contrary also 
happens, namely, that we fear an evil which will certainly come, and our 
fear vanishes when we hear false tidings; thus imaginations do not vanish 
at the presence of the truth, in virtue of its being true, but because 
other imaginations, stronger than the first, supervene and exclude the 
present existence of that which we imagined, as I have shown in II:.xvii.



Prop. II. We are only passive, in so far as 
we are apart of Nature, which cannot be 
conceived by itself without other parts.

Proof.- We are said to be passive, when something arises in us, whereof 
we are only a partial cause (III:Def.ii.), that is (III:Def.i.), something 
which cannot be deduced solely from the laws of our nature. We are passive 
therefore in so far as we are a part of Nature, which cannot be conceived 
by itself without other parts. Q.E.D.



Prop. III. The force whereby a man persists 
in existing is limited, and is infinitely 
surpassed by the power of external causes.

Proof.-This is evident from the axiom of this part. For, when man is 
given, there is something else - say A - more powerful; when A is given, 
there is something else - say B - more powerful than A, and so on to 
infinity; thus the power of man is limited by the power of some other 
thing, and is infinitely surpassed by the power of external causes. Q.E.D.



Prop. IV. It is impossible, that man should 
not be a part of Nature, or that he should 
be capable of undergoing no changes, save 
such as can be understood through his nature 
only as their adequate cause.

Proof.- The power, whereby each particular thing, and consequently man, 
preserves his being, is the power of God or of Nature (I:xxiv.Coroll.); 
not in so far as it is infinite, but in so far as it can be explained by 
the actual human essence (III:vii.). Thus the power of man, in so far 
as it is explained through his own actual essence, is a part of the 
infinite power of God or Nature, in other words, of the essence thereof 
(I:xxxiv.). This was our first point. Again, if it were possible, that man 
should undergo no changes save such as can be understood solely through 
the nature of man, it would follow that he would not be able to die, but 
would always necessarily exist; this would be the necessary consequence 
of a cause whose power was either finite or infinite; namely, either of 
man's power only, inasmuch as he would be capable of removing from himself 
all changes which could spring from external causes; or of the infinite 
power of Nature, whereby all individual things would be so ordered, that 
man should be incapable of undergoing any changes save such as tended 
towards his own preservation. But the first alternative is absurd (by the 
last Prop., the proof of which is universal, and can be applied to all 
individual things). Therefore, if it be possible, that man should not be 
capable of undergoing any changes, save such as can be explained solely 
through his own nature, and consequently that he must always (as we have 
shown) necessarily exist; such a result must follow from the infinite 
power of God, and consequently (I:xvi.) from the necessity of the divine 
nature, in so far as it is regarded as affected by the idea of any given 
man, the whole order of nature as conceived under the attributes of 
extension and thought must be deducible. It would therefore follow (I:xxi.) 
that man is infinite, which (by the first part of this proof) is absurd.
It is, therefore, impossible, that man should not undergo any changes save 
those whereof he is the adequate cause. Q.E.D.

Corollary.- Hence it follows, that man is necessarily always a prey to 
his passions, that he follows and obeys the general order of nature, and 
that he accommodates himself thereto, as much as the nature of things 
demands.



Prop. V. The power and increase of every 
passion, and its persistence in existing 
are not defined by the power, whereby we 
ourselves endeavour to persist in existing, 
but by the power of an external cause 
compared with our own.

Proof.- The essence of a passion cannot be explained through our 
essence alone (III:Def.i.&.ii.), that is (III:vii.), the power of 
a passion cannot be defined by the power, whereby we ourselves 
endeavour to persist in existing, but (as is shown in II:xvi.) must 
necessarily be defined by the power of an external cause compared 
with our own. Q.E.D. 



Prop. VI. The force of any passion or emotion 
can overcome the rest of a man's activities or 
power, so that the emotion becomes obstinately 
fixed to him. 

Proof.- The force and increase of any passion and its persistence in 
existing are defined by the power of an external cause compared with 
our own (by the foregoing Prop.); therefore (IV:iii.) it can overcome a 
man's power, &e. Q.E.D.



Prop. VII. An emotion can only be controlled 
or destroyed by another emotion contrary 
thereto, and with more power for controlling 
emotion.

Proof.- Emotion, in so far as it is referred to the mind, is an idea, 
whereby the mind affirms of its body a greater or less force of existence 
than before (cf. the general Definition of the Emotions at the end of 
Part III.) When, therefore, the mind is assailed by any emotion, the 
body is at the same time affected with a modification whereby its power 
of activity is increased or diminished. Now this modification of the body 
(IV:v.) receives from its cause the force for persistence in its being; 
which force can only be checked or destroyed by a bodily cause (II:vi.), 
in virtue of the body being affected with a modification contrary to 
(III:v.) and stronger than itself (IV.Ax.); wherefore (II:xii.) the mind 
is affected by the idea of a modification contrary to, and stronger than 
the former modification, in other words, (by the general definition 
of the emotions) the mind will be affected by an emotion contrary to and 
stronger than the former emotion, which will exclude or destroy the 
existence of the former emotion; thus an emotion cannot be destroyed nor 
controlled except by a contrary and stronger emotion. Q.E.D.

Corollary.- An emotion, in so far as it is referred to the mind, can 
only be controlled or destroyed through an idea of a modification of 
the body contrary to, and stronger than, that which we are undergoing. 
For the emotion which we undergo can only be checked or destroyed by an 
emotion contrary to, and stronger than, itself, in other words, (by the 
general Definition of the Emotions) only by an idea of a modification 
of the body contrary to, and stronger than, the modification which we 
undergo.



Prop. VIII. The knowledge of good and evil 
is nothing else but the emotions of pleasure 
or pain, in so far as we are conscious 
thereof.

Proof.- We call a thing good or evil, when it is of service or the 
reverse in preserving our being (IV:Def.i.&.ii.), that is (III:vii.), 
when it increases or diminishes, helps or hinders, our power of activity. 
Thus, in so far as we perceive that a thing affects us with pleasure or 
pain, we call it good or evil; wherefore the knowledge of good and evil 
is nothing else but the idea of the pleasure or pain, which necessarily 
follows from that pleasurable or painful emotion (II:xxii.). But this idea 
is united to the emotion in the same way as mind is united to body 
(II:xxi.); that is, there is no real distinction between this idea and 
the emotion or idea of the modification of the body, save in conception 
only. Therefore the knowledge of good and evil is nothing else but the 
emotion, in so far as we are conscious thereof. Q.E.D.



Prop. IX. An emotion, whereof we conceive 
the cause to be with us at the present time, 
is stronger than if we did not conceive the 
cause to be with us.

Proof.- Imagination or conception is the idea, by which the mind regards 
a thing as present (II:xvii.note), but which indicates the disposition of 
the mind rather than the nature of the external thing (II:xvi.Coroll.ii). 
An emotion is therefore a conception, in so far as it indicates the 
disposition of the body. But a conception (by II:xvii.) is stronger, 
so long as we conceive nothing which excludes the present existence 
of the external object; wherefore an emotion is also stronger or more 
intense, when we conceive the cause to be with us at the present time, 
than when we do not conceive the cause to be with us. Q.E.D.

Note.- When I said above in III:xviii. that we are affected by the image 
of what is past or future with the same emotion as if the thing conceived 
were present, I expressly stated, that this is only true in so far as we 
look solely to the image of the thing in question itself ; for the thing's 
nature is unchanged, whether we have conceived it or not; I did not deny 
that the image becomes weaker, when we regard as present to us other 
things which exclude the present existence of the future object: I did 
not expressly call attention to the fact, because I purposed to treat 
of the strength of the emotions in this part of my work.

Corollary.- The image of something past or future, that is, of a thing 
which we regard as in relation to time past or time future, to the 
exclusion of time present, is, when other conditions are equal, weaker 
than the image of something present; consequently an emotion felt towards 
what is past or future is less intense, other conditions being equal, 
than an emotion felt towards something present.



Prop. X. Towards something future, which we 
conceive as close at hand, we are affected 
more intensely, than if we conceive that 
its time for existence is separated from 
the present by a longer interval; so too 
by the remembrance of what we conceive to 
have not long passed away we are affected 
more intensely, than if we conceive that 
it has long passed away. 

Proof.- In so far as we conceive a thing as close at hand, or not long 
passed away, we conceive that which excludes the presence of the object 
less, than if its period of future existence were more distant from the 
present, or if it had long passed away (this is obvious) therefore (by the 
foregoing Prop.) we are, so far, more intensely affected towards it. Q.E.D.

Corollary.- From the remarks made in IV:Def.vi. of this part it follows 
that, if objects are separated from the present by a longer period than 
we can define in conception, though their dates of occurrence be widely 
separated one from the other, they all affect us equally faintly.



Prop. XI. An emotion towards that which 
we conceive as necessary is, when other 
conditions are equal, more intense than 
an emotion towards that which impossible, 
or contingent, or non-necessary.

Proof.- In so far as we conceive a thing to be necessary, we, to that 
extent, affirm its existence; on the other hand we deny a thing's 
existence, in so far as we conceive it not to be necessary :xxxiii.note.i.); 
wherefore (IV.ix.) an emotion towards that which is necessary is, other 
conditions being equal, more intense than an emotion that which is 
non-necessary. Q.E.D.



Prop. XII. An emotion towards a thing, 
which we know not to exist at the present 
time, and which we conceive as possible, 
is more intense, other conditions being 
equal, than an emotion towards a thing 
contingent.

Proof.- In so far as we conceive a thing as contingent, we are affected 
by the conception of some further thing, which would assert the existence 
of the former (IV:Def.iii.); but, on the other hand, we (by hypothesis) 
conceive certain things, which exclude its present existence. But, in 
so far as we conceive a thing to be possible in the future, we there by 
conceive things which assert its existence (IV:iv.), that is (III:xviii.), 
things which promote hope or fear: wherefore an emotion towards something 
possible is more vehement. Q.E.D.

Corollary.- An emotion towards a thing, which we know not to exist in the 
present, and which we conceive as contingent, is far fainter, than if we 
conceive the thing to be present with us.

Proof.- Emotion towards a thing, which we conceive to exist, is more 
intense than it would be, if we conceived the thing as future V:ix.Coroll.), 
and is much more vehement, than if the future time be conceived as far 
distant from the present (IV:x.). Therefore an emotion towards a thing, 
whose period of existence we conceive to be far distant from the present, 
is far fainter, than if we conceive the thing as present; it is, 
nevertheless, more intense, than if we conceived the thing as contingent, 
wherefore an emotion towards a thing, which we regard as contingent, 
will be far fainter, than if we conceived the thing to be present with us. 
Q.E.D.



Prop. XIII. Emotion towards a thing contingent, 
which we know not to exist in the present, is, 
other conditions being equal, fainter than an 
emotion towards a thing past.

Proof.- In so far as we conceive a thing as contingent, we are not 
affected by the image of any other thing, which asserts the existence 
of the said thing (IV:Def.iii.), but, on the other hand (by hypothesis), 
we conceive certain things excluding its present existence. But, in so 
far as we conceive it in relation to time past, we are assumed to 
conceive something, which recalls the thing to memory, or excites the 
image thereof (II:xviii.&Note), which is so far the same as regarding 
it as present (II:xvii.Coroll.). Therefore (IV:ix.) an emotion towards a 
thing contingent, which we know does not exist in the present, is fainter, 
other conditions being equal, than an emotion towards a thing past. Q.E.D.



Prop. XIV. A true knowledge of good and evil 
cannot check any emotion by virtue of being true, 
but only in so far as it is considered as an emotion.

Proof.- An emotion is an idea, whereby the mind affirms of its body a 
greater or less force of existing than before (by the general Definition 
of the Emotions); therefore it has no positive quality, which can be 
destroyed by the presence of what is true; consequently the knowledge 
of good and evil cannot, by virtue oi being true, restrain any emotion.  
But, in so far as such knowledge is an emotion (IV:viii.) if it have 
more strength for restraining emotion, it will to that extent be able 
to restrain the given emotion. Q.E.D.



Prop. XV. Desire arising from the 
knowledge of good and bad can be 
quenched or checked by many of the 
other desires arising from the 
emotions whereby we are assailed.

Proof.- From the true knowledge of good and evil, in so far as it is an 
emotion, necessarily arises desire (Def. of the Emotions, i.), the strength 
of which is proportioned to the strength of the emotion wherefrom it arises 
(III:xxxvii.). But, inasmuch as this desire arises (by hypothesis) from the 
fact of our truly understanding anything, it follows that it is also 
present with us, in so far as we are active (III:i.), and must therefore 
be understood through our essence only (III:Def.ii.); consequently 
(III:vii.) its force and increase can be defined solely by human power. 
Again, the desires arising from the emotions whereby we are assailed are 
stronger, in proportion as the said emotions are more vehement; wherefore 
their force and increase must be defined solely by the power of external 
causes, which, when compared with our own power, indefinitely surpass it 
(IV:iii.); hence the desires arising from like emotions may be more 
vehement, than the desire which arises from a true knowledge of good and 
evil, and may, consequently, control or quench it. Q.E.D.



Prop. XVI. Desire arising from the knowledge 
of good and evil, in so far as such knowledge 
regards what is future, may be more easily 
controlled or quenched, than the desire for 
what is agreeable at the present moment.

Proof.- Emotion towards a thing, which we conceive as future, is fainter 
than emotion towards a thing that is present (IV:ix.Coroll.). But desire, 
which arises from the true knowledge of good and evil, though it be 
concerned with things which are good at the moment, can be quenched 
or controlled by any headstrong desire (by the last Prop., the proof 
whereof is of universal application). Wherefore desire arising from 
such knowledge, when concerned with the future, can be more easily 
controlled or quenched, &c. Q.E.D.



Prop. XVII. Desire arising from the true 
knowledge of good and evil, in so far as 
such knowledge is concerned with what is 
contingent, can be controlled far more 
easily still, than desire for things 
that are present.

Proof.- This Prop. is proved in the same way as the last Prop. from 
IV:xii.Coroll.

Note.- 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: 
(Ov. Met. vii.20, "Video meliora proboque, Deteriora sequor.")

    The better path I gaze at and approve, 

   The worse - I follow."
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.



Prop. XVIII. Desire arising from pleasure is, 
other conditions being equal, stronger than 
desire arising from pain.

Proof.- Desire is the essence of a man (Def. of the Emotions, i.), 
that is, the endeavour whereby a man endeavours to persist in his own 
being. Wherefore desire arising from pleasure is, by the fact of 
pleasure being felt, increased or helped; on the contrary, desire 
arising from pain is, by the fact of pain being felt, diminished or 
hindered; hence the force of desire arising from pleasure must be 
defined by human power together with the power of an external cause, 
whereas desire arising from pain must be defined by human power only. 
Thus the former is the stronger of the two. Q.E.D.

Note.- In these few remarks I have explained the causes of human infirmity 
and inconstancy, and shown why men do not abide by the precepts of reason. 
It now remains for me to show what course is marked out for us by reason, 
which of the emotions are in harmony with the rules of human reason, and 
which of them are contrary thereto.

But, before I begin to prove my Propositions in detailed geometrical 
fashion, it is advisable to sketch them briefly in advance, so that 
everyone may more readily grasp my meaning.

As reason makes no demands contrary to nature, it demands, that every 
man should love himself, should seek that which is useful to him - I mean, 
that which is really useful to him, should desire everything which really 
brings man to greater perfection, and should, each for himself, endeavour 
as far as he can to preserve his own being. This is as necessarily true, 
as that a whole is greater than its part. (Cf. III:iv.)

Again, as virtue is nothing else but action in accordance with the 
laws of one's own nature (IV:Def.viii.), and as no one endeavours to 
preserve his own being, except in accordance with the laws of his own 
nature, it follows, first, that the foundation of virtue is the endeavour 
to preserve one's own being, and that happiness consists in man's power 
of preserving, his own being; secondly, that virtue is to be desired for 
its own sake, and that there is nothing more excellent or more useful to 
us, for the sake of which we should desire it; thirdly and lastly that 
suicides are weak-minded, and are overcome by external causes repugnant to 
their nature. Further, it follows from Postulate iv. Part.II., that we can 
never arrive at doing without all external things for the preservation of 
our being or living, so as to have no relations with things 
which are outside ourselves. Again, if we consider our mind, we see that 
our intellect would be more imperfect, if mind were alone, and could 
understand nothing besides itself. There are, then, many things outside 
ourselves, which are useful to us, and are, therefore, to be desired. 
Of such none can be discerned more excellent, than those which are in 
entire agreement with our nature. For if, for example, two individuals 
of entirely the same nature are united, they form a combination twice 
as powerful as either of them singly.

Therefore, to man there is nothing more useful than man - nothing, 
I repeat, more excellent for preserving their being can be wished for 
by men, than that all should so in all points agree, that the minds and 
bodies of all should form, as it were, one single mind and one single 
body, and that all should, with one consent, as far as they are able, 
endeavour to preserve their being, and all with one consent seek what is 
useful to them all. Hence, men who are governed by reason - that is, who 
seek what is useful to them in accordance with reason, desire for 
themselves nothing, which they do not also desire for the rest of mankind, 
and, consequently, are just, faithful, and honourable in their conduct.

Such are the dictates of reason, which I purposed thus briefly to 
indicate, before beginning to prove them in greater detail. I have taken 
this course, in order, if possible, to gain the attention of those who 
believe, that the principle that every man is bound to seek what is useful 
for himself is the foundation of impiety, rather than of piety and virtue. 

Therefore, after briefly showing that the contrary is the case, I go 
on to prove it by, the same method, as that whereby I have hitherto 
proceeded.



Prop. XIX. Every man, by the laws of his 
nature, necessarily desires or shrinks 
from that which he deems to be good or bad.

Proof.- The knowledge of good and evil is (IV:viii.) the emotion of 
pleasure or pain, in so far as we are conscious thereof; therefore, 
every man necessarily desires what he thinks good, and shrinks from 
what he thinks bad. Now this appetite is nothing else but man's nature 
or essence (Cf. the Definition of Appetite, III.ix.note, and Def. of 
the Emotions, i.). Therefore, every man, solely by the laws of his 
nature, desires the one, and shrinks from the other, &c. Q.E.D. 



Prop. XX. The more every man endeavours, 
and is able to seek what is useful to him - 
in other words, to preserve his own being - 
the more is he endowed with virtue; on the 
contrary, in proportion as a man neglects 
to seek what is useful to him, that is, to 
preserve his own being, he is wanting in power.

Proof.- Virtue is human power, which is defined solely by man's essence 
(IV:Def.viii.), that is, which is defined solely by the endeavour made by 
man to persist in his own being. Wherefore, the more a man endeavours, 
and is able to preserve his own being, the more is he endowed with virtue, 
and, consequently (III:iv.&,vi.), in so far as a man neglects to 
preserve his own being, he is wanting in power. Q.E.D. 

Note.- No one, therefore, neglects seeking his own good, or preserving his 
own being, unless he be overcome by causes external and foreign to his 
nature. No one, I say, from the necessity of his own nature, or otherwise 
than under compulsion from external causes, shrinks from food, or kills 
himself: which latter may be done in a variety of ways. A man, for 
instance, kills himself under the compulsion of another man, who twists 
round his right hand, wherewith he happened to have taken up a sword, and 
forces him to turn the blade against his own heart; or, again, he may be 
compelled, like Seneca, by a tyrant's command, to open his own veins - 
that is, to escape a greater evil by incurring, a lesser; or, lastly, 
latent external causes may so disorder his imagination, and so affect his 
body, that it may assume a nature contrary to its former one, and whereof 
the idea cannot exist in the mind (III:x.) But that a man, from the 
necessity of his own nature, should endeavour to become non-existent, is 
as impossible as that something should be made out of nothing, as everyone 
will see for himself, after a little reflection.



Prop. XXI. No one can desire to be blessed, 
to act rightly, and to live rightly, without 
at the same time wishing to be, act, and to 
live - in other words, to actually exist.

Proof.- The proof of this proposition, or rather the proposition itself, 
is self-evident, and is also plain from the definition of desire. For the 
desire of living, acting, &C., blessedly or rightly, is (Def. of the 
Emotions, i.) the essence of man - that is (III:vii.), the endeavour 
made by everyone to preserve his own being. Therefore, no one can 
desire, &c. Q.E.D.



Prop. XXII. No virtue can be conceived 
as prior to this endeavour to preserve 
one's own being.

Proof.- The effort for self-preservation is the essence of a thing 
(III:vii.); therefore, if any virtue could be conceived as prior 
thereto, the essence of a thing would have to be conceived as 
prior to itself, which is obviously absurd. Therefore no virtue, &c. 
Q.E.D.

Corollary.- The effort for self-preservation is the first and only 
foundation of virtue. For prior to this principle nothing can be 
conceived, and without it no virtue can be conceived.



Prop. XXIII. Man, in so far as he is 
determined to a particular action 
because he has inadequate ideas, 
cannot be absolutely said to act in 
obedience to virtue; he can only be 
so described, in so far as he is 
determined for the action because 
he understands.

Proof.- In so far as a man is determined to an action through having 
inadequate ideas, he is passive (III:i.), that is (III:Def.i., &iii.), 
he does something, which cannot be perceived solely through his essence, 
that is (by IV:Def.viii.), which does not follow from his virtue. But, 
in so far as he is determined for an action because he understands, he 
is active; that is, he does something, which is perceived through his 
essence alone, or which adequately follows from his virtue. Q.E.D.



Prop. XXIV. To act absolutely in obedience 
to virtue is in us the same thing as to act, 
to live, or to preserve one's being (these 
three terms are identical in meaning) in 
accordance with the dictates of reason on the 
basis of seeking what is useful to one's self.

Proof.- To act absolutely in obedience to virtue is nothing else but 
to act according to the laws of one's own nature. But we only act, in 
so far as we understand (III:iii.) : therefore to act in obedience to 
virtue is in us nothing else but to act, to live, or to preserve one's 
being in obedience to reason, and that on the basis of seeking what is 
useful for us (IV:xxii.Coroll.). Q.E.D.



Prop. XXV. No one wishes to preserve his 
being for the sake of anything else.

Proof.- The endeavour, wherewith everything endeavours to persist in its 
being, is defined solely by the essence of the thing itself (III:vii.); 
from this alone, and not from the essence of anything else, it necessarily 
follows (III:vi.) that everyone endeavours to preserve his being. 
Moreover, this proposition is plain from IV:xxii.Coroll., for if a man 
should endeavour to preserve his being for the sake of anything else, the 
last-named thing would obviously be the basis of virtue, which, by the 
foregoing corollary, is absurd. Therefore no one, &c. Q.E.D.



Prop. XXVI. Whatsoever we endeavour in 
obedience to reason is nothing further 
than to understand; neither does the mind, 
in so far as it makes use of reason, judge 
anything to be useful to it, save such 
things as are conducive to understanding.

Proof.- The effort for self-preservation is nothing else but the essence 
of the thing in question (III:vii.), which, in so far as it exists such 
as it is, is conceived to have force for continuing in existence (III:vi.) 
and doing such things as necessarily follow from its given nature (see the 
Def. of Appetite, II:ix.Note). But the essence of reason is nought else but 
our mind, in so far as it clearly and distinctly understands (see the 
definition in II:xl.Note:ii.) ; therefore (III:xl.) whatsoever we endeavour 
in obedience to reason is nothing else but to understand. Again, since this 
effort of the mind wherewith the mind endeavours, in so far as it reasons, 
to preserve its own being is nothing else but understanding; this effort 
at understanding is (IV:xxii.Coroll.) the first and single basis of virtue, 
nor shall we endeavour to understand things for the sake of any ulterior 
object (IV:xxv.); on the other hand, the mind, in so far as it reasons, 
will not be able to conceive any good for itself, save such things as are 
conducive to understanding.



Prop. XXVII. We know nothing to be certainly 
good or evil, save such things as really 
conduce to understanding, or such as are 
able to hinder us from understanding.

Proof.- The mind, in so far as it reasons, desires nothing beyond 
understanding, and judges nothing to be useful to itself, save such 
things as conduce to understanding (by the foregoing Prop.). But the 
mind (II:xli.&Note) cannot possess certainty concerning anything, 
except in so far as it has adequate ideas, or (what by II:xl.Note, 
is the same thing) in so far as it reasons. Therefore we know nothing 
to be good or evil save such things as really conduce, &c. Q.E.D.



Prop. XXVIII. The mind's highest good is 
the knowledge of God, and the mind's 
highest virtue is to know God.

Proof.- The mind is not capable of understanding anything higher than God, 
that is (I:Def.vi.), than a Being absolutely infinite, and without which 
(I:xv.) nothing can either be or be conceived; therefore (IV:xxvi., 
&xxvii.), the mind's highest utility or (IV:Def.i.) good is the knowledge
of God. Again, the mind is active, only in so far as it understands, and 
only to the same extent can it be said absolutely to act virtuously. The 
mind's absolute virtue is therefore to understand. Now, as we have already 
shown, the highest that the mind can understand is God; therefore the 
highest virtue of the mind is to understand or to know God. Q.E.D.



Prop. XXIX. No individual thing, which is 
entirely different from our own nature, 
can help or check our power of activity, and 
absolutely nothing can do us good or harm, 
unless it has something in common with our nature.

Proof.- The power of every individual thing, and consequently the power of 
man, whereby he exists and operates, can only be determined by an 
individual thing (I:xxviii.), whose nature (II:vi.) must be understood 
through the same nature as that, through which human nature is conceived. 
Therefore our power of activity, however it be conceived, can be determined 
and consequently helped or hindered by the power of any other individual 
thing, which has something in common with us, but not by the power of 
anything, of which the nature is entirely different from our own; and 
since we call good or evil that which is the cause of pleasure or pain 
(IV:viii.), that is (III:xi.Note), which increases or diminishes, helps 
or hinders, our power of activity; therefore, that which is entirely, 
different from our nature can neither be to us good nor bad. Q.E.D.



Prop. XXX. A thing cannot be bad for us 
through the quality which it has in common 
with our nature, but it is bad for us in so 
far as it is contrary to our nature. 

Proof.- We call a thing bad when it is the cause of pain (IV:viii.), that 
is (by the Def., which see in III:xi.Note), when it diminishes or checks 
our power of action. Therefore, if anything were bad for us through that 
quality which it has in common with our nature, it would be able 
itself to diminish or check that which it has in common with our nature, 
which (III:iv.) is absurd. Wherefore nothing can be bad for us through 
that quality which it has in common with us, but, on the other hand, in 
so far as it is bad for us, that is (as we have just shown), in so far as  
it can diminish or check our power of action, it is contrary to our nature. 
Q.E.D.



Prop. XXXI. In so far as a thing is in harmony 
with our nature, it is necessarily good.

Proof.- In so far as a thing is in harmony with our nature, it cannot be 
bad for it. It will therefore necessarily be either good or indifferent. 
If it be assumed that it be neither good nor bad, nothing will follow from 
its nature (IV:Def.i.), which tends to the preservation of our nature, 
that is (by the hypothesis), which tends to the preservation of the thing 
itself; but this (III:vi.) is absurd; therefore, in so far as a thing is 
in harmony with our nature, it is necessarily good. Q.E.D.

Corollary.- Hence it follows, that, in proportion as a thing is in harmony 
with our nature, so is it more useful or better for us, and vice versa, in 
proportion as a thing is more useful for us, so is it more in harmony with 
our nature. For, in so far as it is not in harmony with our nature, it 
will necessarily be different therefrom or contrary thereto. If different, 
it can neither be good nor bad (IV:xxix.); if contrary, it will be contrary 
to that which is in harmony with our nature, that is, contrary to what is 
good - in short, bad. Nothing, therefore, can be good, except in so far as 
it is in harmony with our nature; and hence a thing is useful, in proportion 
as it is in harmony with our nature, and vice versa. Q.E.D.



Prop. XXXII. In so far as men are a prey 
to passion, they cannot, in that respect, 
be said to be naturally in harmony.

Proof. Things, which are said to be in harmony naturally, are understood to 
agree in power (III:vii.), not in want of power or negation, and 
consequently not in passion (III:iii.Note); wherefore men, in so far as 
they are a prey to their passions, cannot be said to be naturally in 
harmony. Q.E.D.

Note.- This is also self-evident; for, if we say that white and black only 
agree in the fact that neither is red, we absolutely affirm that the do not 
agree in any respect. So, if we say that a man and a stone only agree in the 
fact that both are finite - wanting in power, not existing by the necessity 
of their own nature, or, lastly, indefinitely surpassed by the power of 
external causes - we should certainly affirm that a man and a stone are in 
no respect alike; therefore, things which agree only in negation, or in 
qualities which neither possess, really agree in no respect.



Prop. XXXIII. Men can differ in nature, 
in so far as they are assailed by those 
emotions, which are passions, or passive 
states; and to this extent one and the 
same man is variable and inconstant.

Proof.- The nature or essence of the emotions cannot be explained solely 
through our essence or nature (III:Def.i.&ii.), but it must be defined by 
the power, that is (III:vii.), by the nature of external causes in 
comparison with our own; hence it follows, that there are as many kinds of 
each emotion as there are external objects whereby we are affected 
(III:lvi.), and that men may be differently affected by one and the same 
object (III:li), and to this extent differ in nature; lastly, that one and 
the same man may be differently affected towards the same object, and may 
therefore be variable and inconstant. Q.E.D.



Prop. XXXIV. In so far as men are assailed 
by emotions which are passions, they can be 
contrary one to another.

Proof.- A man, for instance Peter, can be the cause of Paul's feeling pain, 
because he (Peter) possesses something similar to that which Paul hates 
(III:xvi.), or because Peter has sole possession of a thing which Paul also 
loves (III:xxxii.&Note), or for other causes (of which the chief are 
enumerated in III:lv.Note) ; it may therefore happen that Paul should hate 
Peter (Def. of Emotions: vii.), consequently it may easily happen also, that 
Peter should hate Paul in return, and that each should endeavour to do the 
other an injury, (III:xxxix.), that is (IV:xxx.), that they should be 
contrary one to another. But the emotion of pain is always a passion 
or passive state (III:lix.); hence men, in so far as they are assailed by 
emotions which are passions, can be contrary one to another. Q.E.D.

Note.- I said that Paul may hate Peter, because he conceives that Peter 
possesses something which he (Paul) also loves; from this it seems, at first 
sight, to follow, that these two men, through both loving the same thing, 
and, consequently, through agreement of their respective natures, stand in 
one another's way; if this were so, II:xxx. and II:xxxi. would be untrue. 
But if we give the matter our unbiased attention, we shall see that the 
discrepancy vanishes. For the two men are not in one another's way in 
virtue of the agreement of their natures, that is, through both loving the 
same thing, but in virtue of one differing from the other. For, in so far 
as each loves the same thing, the love of each is fostered thereby 
(III:xxxi.), that is (Def. of the Emotions: vi.) the pleasure of each is 
fostered thereby. Wherefore it is far from being the case, that they are 
at variance through both loving the same thing, and through the agreement 
in their natures. The cause for their opposition lies, as I have said, 
solely in the fact that they are assumed to differ. For we assume that 
Peter has the idea of the loved object as already in his possession, while 
Paul has the idea of the loved object as lost. Hence the one man will be 
affected with pleasure, the other will be affected with pain, and thus they 
will be at variance one with another. We can easily show in like manner, 
that all other causes of hatred depend solely on differences, and not on 
the agreement between men's natures.