Ethics

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. and 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 II. 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. Deff. i. and 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. Deff. i. and 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 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 possible, 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 (I. 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 (IV. 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. and 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 of 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 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:[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.

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. and 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.

Deff. i., and 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, III. 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 (II. 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., xliii. and 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. and 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