Kenny Anthony. An Illustrated Brief History of Western Philosophy

Подождите немного. Документ загружается.

philosophy in the thirteenth century

154

unmatched before or since: by patient examination he refuted not only Aristo-

telian arguments for the eternity of the world, but also arguments put forward

by Muslims and Christians to show that the world was created in time. Neither

proposition, he maintained, could be proved by reason, and philosophy must be

agnostic on the issue; we should believe that creation took place in time simply

because the book of Genesis told us so.

Matter, Form, Substance, and Accident

In metaphysics Aquinas was a faithful follower of Aristotle – though not a slavish

one, as the example of the eternal universe illustrates. He accepted the analysis of

material bodies in terms of matter and form, and the thesis that change is to be

explained as the reception of different successive forms in the same matter. He

also accepted the Aristotelian doctrine that matter is the principle of individuation:

if two pebbles on the beach resemble each other in every possible way, they will

not differ at all in form, but they will be two pebbles and not one pebble because

they are two different chunks of matter.

These Aristotelian theses gave rise to problems in connection with the angels

of which the Bible speaks and which Christian tradition had come to regard as

non-corporeal. Aquinas regarded as implausible Bonaventure’s suggestion that

angels too contained matter, but matter that was spiritual. Instead, he regarded

angels as being pure immaterial forms. But if matter is the principle of individua-

tion, how can there be more than one immaterial angel? Aquinas’ answer was that

each angel was a form of a different kind, a species all to himself. So Michael and

Gabriel would differ from each other not as Peter differs from Paul, but as a sheep

differs from a cow.

Matter and form are the concepts used by Aristotelians to analyse substantial

change, the type of change when one kind of thing turns into another. To analyse

the less drastic change when one and the same thing gains or loses a transient

property (e.g. grows taller or becomes sunburnt), the concepts used were sub-

stance and accident. One of the most extraordinary, but also inﬂuential, uses to

which Thomas put Aristotle’s concepts was in his explanation of the nature of the

Christian eucharist, the sacrament which perpetuated the supper in which Jesus

took bread and said ‘this is my body’, and spoke of wine as being his blood.

Aquinas maintained that when Jesus’ words were repeated by the priest, the

substance of bread and wine turned into the substance of Christ’s body and

blood. This change was called ‘transubstantiation’.

Transubstantiation is a unique conversion, Aquinas says, a turning of one thing

into another which has no parallel. In all other cases, where A turns into B there

is some stuff which is ﬁrst A-ish and then B-ish; in Aristotelian terms, the same

matter is ﬁrst informed with A-ishness, and then with B-ishness. But in the

AIBC08 22/03/2006, 11:02 AM154

philosophy in the thirteenth century

155

eucharistic conversion there is no parcel of stuff which is ﬁrst bread and then

Christ’s body; not only does one form give way to another, but one bit of matter

gives way to another. In an ordinary change, where the form of A-ishness gives

way to the form of B-ishness, we have a transformation. In the eucharist we have

not just one form giving way to another, but one substance giving way to another:

not just transformation but transsubstantiation.

We may wonder whether anything is now left here of the notion of turning

into, and indeed why the notion is introduced at all into the discussion of the

eucharist. There is no mention in scriptural references of anything turning into

anything else; why is there in Aquinas?

The notion is introduced as the only possible explanation of the presence of

Christ’s body under the appearances of bread and wine. After the consecration it

is true to say that Christ is in such-and-such a place; on the altar, say, in the church

of Bolsena. Now there are only three ways, Aquinas says, in which something can

begin to exist in a place in which it did not exist before. Either it moves to that

place from another place, or it is created in that place, or something which is al-

ready in that place turns, or is turned, into it. But Christ’s body does not move into

the place where the eucharistic appearances are, nor is it created, since it already

exists. Therefore something – to wit, the bread and wine – is turned into it.

What remain, visible and tangible on the altar, are, Aquinas says, the accidents

of bread and wine – shape, colour and so on; they remain, according to Aquinas,

without a substance to inhere in. Aquinas did not believe that the accidents after

consecration inhered in the substance of Christ’s body. If this were so then, for

example, the size and shape which the bread once had would become the size

and shape of Christ’s body, which would mean that he was round and two inches

in diameter, and so on.

St Thomas attached great importance to the doctrine of transubstantiation, and

he expressed his devotion to the eucharist not only in theological prose but also

in the devotional hymns which he wrote for the new feast of Corpus Christi.

A verse of one of them has been thus translated by Gerard Manley Hopkins.

Seeing, touching, tasting are in thee deceived;

How says trusty hearing? that shall be believed:

What God’s Son has told me, take for truth I do;

Truth himself speaks truly, or there’s nothing true.

Hopkins’ verse is more mannered than Aquinas’, but it represents accurately

the sense of the original. The verse is surprising, because Aquinas’ ofﬁcial view is

that in the eucharist there is no deception of the senses: they register accurately

the presence of the accidents, and it is not their job, but the intellect’s, to make

judgements about substance. In this extraordinary case, the intellect may be misled

into judging the presence of bread: but not if it listens to the word of God.

AIBC08 22/03/2006, 11:02 AM155

philosophy in the thirteenth century

156

Is the concept of accidents inherent in no substance a coherent one? On the

one hand, the idea of the Cheshire cat’s grin without the cat seems the very

quintessence of absurdity. On the other hand, to take an example of Aquinas’

own, a smell of wine can hang around after the wine has all been drunk. And

perhaps the colour of the sky is an example of an accident without a substance:

the blueness of the sky is not the blueness of anything real.

However, the principle that the accidents inhere in no substance leaves one

problem which may be thought fatal to Aquinas’ account. Among the accidental

categories of Aristotle is the category of place; ‘is on the altar’, for instance, is

an accidental predicate. But if the accidents which once belonged to the bread

do not inhere after consecration in the substance of Christ, then it appears that it

by no means follows from the presence of the host upon the altar that Christ is

present on the altar. Thus the doctrine of transubstantiation appears in the end to

fail to secure that for which alone it was originally introduced, namely the real

presence of Christ’s body under the sacramental appearances.

Aquinas on Essence and Existence

Difﬁculties with the notion of transubstantiation do not, of course, call in ques-

tion the general concepts of substance and accident outside this particular, and

perhaps perverse, theological application of them. But the Aristotelian analysis of

change raises other problems which Aquinas considers. If accidental change is to

be understood as one and the same substance taking on various accidents, and

substantial change is to be understood as one and the same matter taking on

various substantial forms, should we understand the origin of the material world

itself as being a case of one and the same essence passing from non-existence to

existence? This was not, of course, a question which arose for Aristotle, who did

not believe in creation out of nothing; but some later Aristotelians had posed

the question and answered it in the afﬁrmative. Aquinas ﬁrmly rejects the idea:

creation is totally different from change, and is not to be understood in terms of

existence being fastened on to an essence.

None the less, Aquinas accepted the terminology of essence and existence and

makes frequent use of it in his metaphysics. In all creatures, he taught, essence

and existence were distinct; in God, however, they were identical: God’s essence

was his existence. This is often held to be a sublime metaphysical insight. In fact,

it appears to rest on a confusion.

We should make a distinction between generic and individual essences. If we

understand ‘essence’ in the generic sense (as being the reality which corresponds

to a predicate such as ‘. . . is God’, ‘. . . is human’, ‘. . . is a Labrador’), then it is

true that there is, in all creatures, a real distinction between essence and existence.

That is to say, whether or not there are any instances of a particular kind of thing

AIBC08 22/03/2006, 11:02 AM156

philosophy in the thirteenth century

157

is quite another matter from what are the constituent characteristics of a thing of

that kind – for instance, whether there are or are not unicorns is a different kind

of question from the question whether unicorns are mammals. But if we take

‘essence’ in this sense, then the doctrine that essence and existence are identical in

God is a piece of nonsense: it amounts to saying that the question ‘what kind of

thing is God?’ is to be answered by saying ‘There is a God’.

On the other hand, if we understand ‘essence’ in the individual sense in which

we can speak of the individualized humanity possessed by Socrates and by Socrates

alone, then the doctrine of the real distinction in creatures becomes obscure and

groundless. As Aquinas often insists, for a human being to exist is for it to go on

being a human being; Peter’s existing is the very same thing as Peter’s continuing

to possess his essence; if he ceases to exist he ceases to be a human being and his

individualized essence passes out of the nature of things.

Aquinas’ Philosophy of Mind

In treating of the human mind Aquinas had an exacting task: he wanted to show

that it was possible to accept Aristotle’s psychology without following Averroes in

denying the immortality of the individual human soul. Like Bonaventure, Aquinas

refused to accept the Arab philosophers’ theory that human beings shared a

common universal intellect. The intellect which sets human beings apart from

other animals can be thought of, without too much distortion of Aquinas’ thought,

as the capacity for thinking those thoughts that only a language-user can think.

This power was, for Aquinas, a faculty of the individual human soul. Following

Aristotelian tradition, he distinguished between an active intellect and a receptive

intellect; both of these, he insisted, were powers which each one of us possesses.

The active intellect is the capacity to form universal ideas and to attain necessary

truth. The receptive intellect is the storehouse of ideas and knowledge once

acquired (see Plate 10).

According to Aquinas, the intellect acquires its concepts by reﬂection upon

sensory experience; we have no innate ideas, nor, for everyday knowledge, do we

receive any special divine illumination. Experience is necessary for human acquisi-

tion of concepts, but it is not sufﬁcient; that is why we have a special concept-

forming capacity, the active intellect. We need it, Aquinas thought, because the

material objects of the world we live in are not, in themselves, ﬁt objects for

intellectual understanding. A Platonic Idea, universal, intangible, unchanging,

unique, might be a suitable object for the intellect; but in our world there are no

such things as Platonic Ideas, and if there are any in the mind of God that is no

business of ours in our present lives. So, Aquinas concludes, we need a special

power in order to create what he calls ‘actually thinkable objects’ by abstracting

ideas from our experience of the world. This power is the active intellect.

AIBC08 22/03/2006, 11:02 AM157

philosophy in the thirteenth century

158

Aquinas explains what he means by making a comparison between sight and

thought. Colours are perceptible by the sense of sight: but in the dark, colours

are only potentially, not actually, perceptible. The sense of vision is only actuated

– a person only sees the colours – when light is present to render them actually

perceptible. Similarly, Aquinas says, the things in the physical world are, in them-

selves, only potentially thinkable or intelligible. An animal with the same senses as

ours perceives and deals with the same material objects as we do; but he cannot

have intellectual thoughts about them – he cannot, for instance, have a scientiﬁc

understanding of their nature – for lack of the light cast by the active intellect. We,

because we can abstract ideas from the material conditions of the natural world,

are able not just to perceive, but to think about, and understand, the world.

It is by means of its ideas that the mind understands the world; but this does

not mean that ideas are replicas or pictures of external things from which the

mind reads off their nature. However, because ideas are universal and external

things are particular, it does mean that, for Aquinas, there is no purely intellectual

knowledge of individuals as such. This follows from two Aristotelian theses which

Aquinas accepted: that to understand something is to grasp its form without its

matter; and that matter is the principle of individuation.

If Plato was wrong, as Aquinas thought he was, then there is not, outside the

mind, any such thing as human nature in itself: there is only the human nature of

individual human beings such as Tom, Dick, and Harry. But because the human-

ity of individuals is form embedded in matter, it is not something which can, as

such, be the object of pure intellectual thought. To grasp the humanity of Tom,

the humanity of Dick, and the humanity of Harry we need to call in aid the

senses and the imagination. The humanity of an individual, in Aquinas’ termin-

ology, is ‘thinkable’ (because it is a form), but not ‘actually thinkable’ (because

existing in matter). That is to say, it is, because it is a form, a ﬁt object of the

understanding; but it needs to undergo a metamorphosis if it is to be actually

held in the mind. It is the active intellect which, on the basis of our experience of

individual humans, creates the intellectual object, humanity as such. And human-

ity as such has no existence outside the mind (see Plate 11).

Theorists of the human mind are sometimes grouped into empiricists, rational-

ists, and idealists. Very crudely, empiricists believe that all knowledge of the world

comes from experience; rationalists believe that important knowledge about the

world is inborn; idealists believe that the human mind’s knowledge extends only

to its own ideas. Aquinas’ position differs from each of these, but shares with each

some common ground. Like the empiricists, Aquinas denies that there is innate

knowledge; mind without experience is a tabula rasa, an empty page. But he

agrees with the rationalists against the empiricists that mere experience, of the

kind that humans and animals share, is impotent to write anything on the empty

page. Like the idealists, Aquinas believes that the immediate object of purely

intellectual thought is something which is its own creation, namely, a universal

AIBC08 22/03/2006, 11:02 AM158

philosophy in the thirteenth century

159

concept; but, unlike many idealists, Aquinas believes that a human being, by means

of these universal concepts and with the aid of the senses and the imagination,

can achieve genuine knowledge of the extra-mental world.

Aquinas’ Moral Philosophy

Aquinas’ ethical system is most copiously set out in the Second Part of his

Summa Theologiae. This, which is nearly 900,000 words long, is subdivided into

a ﬁrst part (the Prima Secundae) which contains the General Part of ethics, and

the second part (the Secunda Secundae) which contains detailed teaching on

individual moral topics. The work, in both structure and content, is modelled on

Aristotle’s Nicomachean Ethics, on which at the same time Aquinas wrote a line-

by-line commentary.

Much in Aristotle was very congenial. Like Aristotle Aquinas identiﬁes the

ultimate goal of human life with happiness, and like him he thinks that happiness

cannot be equated with pleasure, riches, honour, or any bodily good, but must

consist in activity in accordance with virtue, especially intellectual virtue. The

intellectual activity which satisﬁes the Aristotelian requirements for happiness is to

be found perfectly only in contemplation of the essence of God; happiness in the

ordinary conditions of the present life must remain imperfect. True happiness,

then, even on Aristotle’s terms, is to be found only in the souls of the blessed in

Heaven. The Saints will in due course receive a bonus of happiness, undreamt of

by Aristotle, in the resurrection of their bodies in glory. Aquinas expounds and

improves upon Aristotle’s account of virtue, action, and emotion before going on

to relate these teachings to the speciﬁcally theological topics of divine law and

divine grace.

Aquinas’ lengthy discussion of human action marks a great advance on Aristotle

or any previous Christian thinker. Aristotle, in his Ethics, introduced the concept

of voluntariness: something was voluntary if it was originated by an agent free

from compulsion or error. In his moral system an important role was also played

by the concept of prohairesis or purposive choice: this was the choice of an action

as part of an overall plan of life. Aristotle’s concept of the voluntary was too

clumsily deﬁned, and his concept of prohairesis too narrowly deﬁned, to demarcate

the everyday moral choices which make up our life. (The fact that there is no

English word corresponding to ‘prohairesis’ is itself a mark of the awkwardness of

the concept; most of Aristotle’s moral terminology has been incorporated into all

European languages.) While retaining Aristotle’s concepts, Aquinas introduced

a new one of intention, which ﬁlled the gap left between the two of them, and

greatly facilitated moral thinking.

In Aquinas’ system there are three types of action. There are those things

which we do for their own sake, wanted as ends in themselves: the pursuit of

AIBC08 22/03/2006, 11:02 AM159

philosophy in the thirteenth century

160

philosophy, for instance. There are those things which we do because they are

means to ends which we want for themselves: taking medicine for the sake of our

health is Aquinas’ example. It is in these actions that we exhibit intention: we

intend to achieve the end by the means. Finally, there are the (perhaps unwanted)

consequences and side-effects which our intentional actions bring about. These

are not intentional, but merely voluntary. Voluntariness, then, is the broadest

category; whatever is intentional is voluntary, but not vice versa. Intention itself,

while covering a narrower area than voluntariness, is a broader concept than

Aristotle’s prohairesis.

Aquinas expounds the relation between intention and morality in the follow-

ing manner. Human acts may be divided into kinds, some of which are good

(e.g. using one’s own property), some bad (e.g. stealing), and some indifferent

(e.g. walking in the country). Every individual concrete action, however, will be

performed in particular circumstances with a particular purpose. For an action

to be good, the kind it belongs to must not be bad, the circumstances must be

appropriate, and the intention must be virtuous. If any of these elements is miss-

ing, the act is evil. Consequently, a bad intention can spoil a good act (almsgiving

out of vainglory) but a good intention cannot redeem a bad act (stealing to give

to the poor).

Aquinas considers the problem of erroneous conscience, the case where some-

one has a false belief about the goodness or badness of a particular action. To do

what one thinks wrong, he says, is always wrong; it is always a bad thing for a

man’s will to disaccord with his reason, even if his reason is in error. Accordingly,

an erroneous conscience always binds us. However, it does not always excuse us.

If the error is due to negligence, then the agent is not excused. Adultery is not

excused by thinking it lawful, for such error is culpable ignorance of the law of

God. But a man who, without negligence, believes another man’s wife to be his

own does not sin by having sex with her.

Aquinas agrees with Abelard that the goodness of a good action derives from

the good will with which it is performed; but he says that will can only be good

if it is willing an action of a kind reason can approve. Moreover, he insists that

good will cannot be fully genuine unless it is put into action when opportunity

arises. A failure to act must be an involuntary failure if it is to be irrelevant to

morality. Thus Aquinas avoids the paradoxical conclusions which brought Abelard’s

theory of intention into disrepute.

The morality of an act, Aquinas says, may be affected by its consequences. He

makes a distinction between the harm which is foreseen and intended, and that

which is foreseen and not intended. As an example of the former he cites the harm

resulting from the actions of a murderer or thief; to illustrate the latter he says,

‘A man, crossing a ﬁeld the more easily to fornicate, may damage what is sown in

the ﬁeld; knowingly, but without a mind to do any damage’. In these cases we

have bad consequences of bad acts, and in each case the sin is aggravated. But

AIBC08 22/03/2006, 11:02 AM160

philosophy in the thirteenth century

161

what about the responsibility of an agent for the bad consequences of good

acts? Aquinas addresses this issue when dealing with the lawfulness of killing in

self defence. Augustine had taught that this was forbidden for a Christian; but

authoritative legal texts said it was lawful to repel force with force. Aquinas says: an

act may have two effects, one intended, and the other beside the intention; thus,

the act of a man defending himself may have two effects, one the preservation of his

own life, the other the death of the attacker. Provided no more violence is used

than necessary, such an act is permissible; however, it is never lawful to intend to

kill another, unless one is acting on public authority, like a soldier or policeman.

From remarks such as this Aquinas’ followers developed the famous doctrine of

double effect. If an act, not evil in itself, has both good and bad effects, then it

may be permissible if (1) the evil effect is not intended, and (2) the good effect is

not produced by means of the bad, and (3) on balance, the good done outweighs

the harm. There are many everyday applications of the principle of double effect:

e.g. there is nothing wrong with appointing the best person to a job, though you

know that by doing so you will give pain to the other candidates. The principle is

fundamental to serious ethical thinking; but for reasons to be discussed later, it

fell into disrepute among moralists in the early modern period.

In the Secunda Secundae Aquinas analyses each individual virtue in turn, and

the vices and sins which conﬂict with it. Here, too, he is following Aristotle; but

there are important additions and modiﬁcations. Christian tradition had added

the three ‘theological’ virtues of faith, hope, and charity to the classical Greek list

of wisdom, temperance, courage, and justice. Aquinas accordingly treats of the

virtue of faith and the sins of unbelief, heresy, and apostasy; of the virtue of hope

and the sins of despair and presumption; and of the virtue of charity and the sins

of hatred, envy, discord and sedition.

Aquinas’ list of moral virtues does not altogether tally with Aristotle’s, though

he works hard to Christianize some of the more pagan characters who appear in

the Nicomachean Ethics. For Christians, for instance, one of the most important

virtues is humility. Aristotle’s good man, on the other hand, is far from humble:

he is great-souled, that is to say he is a highly superior being who is very well

aware of his own superiority to others. In his treatment of humility, Aquinas

comments on the text of St Paul, ‘let each esteem others better than themselves’.

How can this be possible, and if possible, how can it be a virtue? Aquinas sensibly

says that it cannot be a virtue to believe oneself the worst of sinners: if we all did

that, then all but one of us would be believing a falsehood, and it cannot be the

part of virtue to promote false belief. He glosses the text thus: what is good in

each of us comes from God; all we can really call our own is our sinfulness. But

humility does not require, he says, that someone should regard less the gifts of

God in himself than the gifts of God in others.

Aquinas deﬁnes humility as the virtue which restrains the appetite from pursu-

ing great things beyond right reason. It is the virtue which is the moderation of

AIBC08 22/03/2006, 11:02 AM161

philosophy in the thirteenth century

162

ambition – not its contradiction, but its moderation. It is based on, though it is

not identical with, a just appreciation of one’s own defects. Finally, by a remark-

able piece of intellectual legerdemain, Aquinas makes it not only compatible with,

but a counterpart of, the great-souled man’s alleged virtue of magnanimity. Humil-

ity, he says, ensures that one’s ambitions are based on a just assessment of one’s

defects, magnanimity that they are based on a just assessment of one’s gifts.

Aquinas is anxious to reconcile the virtue-based ethic of Aristotle with the

role of divine law in the Christian moral system. In Aristotle it is reason which

sets the goal of action and sets the standard by which actions are to be judged;

according to the Bible, the standard is set by the law. But there is no conﬂict,

because law is a product of reason. Human legislators, the community or its

delegates, use their reason to devise laws for the general good of individual states.

But the world as a whole is ruled by the reason of God. The eternal plan of

providential government, which exists in God as ruler of the universe, is a law

in the true sense. It is a natural law, inborn in all rational creatures in the form

of a natural tendency to pursue the behaviour and goals appropriate to them.

The natural law is simply the sharing, by rational creatures, in the eternal law of

God. It obliges us to love God and our neighbour, to accept the true faith, and

to offer worship.

Many times Aquinas returns to the passage in the ﬁnal book of the Nicomachean

Ethics which values the contemplative life above the active life. He treats it in

several different ways, one of the most interesting of which is his application of

Aristotle’s teaching to the topic of the vocations of various religious orders. All

religious orders, he says, are instituted for the sake of charity: but charity includes

both love of God and love of neighbour. The contemplative orders seek to spend

time on God alone; the active orders seek to serve the needs of their fellows. Now

which are to be preferred, contemplative or active orders? Aquinas draws a dis-

tinction between two kinds of active life. There is one kind of active life which

consists entirely in external actions, such as the giving of alms, or the succour of

wayfarers; but there is another kind of active life which consists in teaching and

preaching. In these activities the religious person is drawing on the fruits of

previous contemplation, passing on to others the truths thus grasped. While the

purely contemplative life is to be preferred to the purely active life, the best life of

all for the religious is the life which includes teaching and preaching. ‘Just as it is

better to light up others than to shine alone, it is better to share the fruits of

one’s contemplation with others than to contemplate in solitude.’ St Thomas

does not specify what religious order he has in mind; but his phrase contemplata

aliis tradere served as a motto for the Dominican Order.

Neither in his lifetime nor for long after his death was Aquinas regarded as a

uniquely authoritative Catholic thinker. Three years after his death a number of

propositions resembling positions he had held were condemned by ecclesiastical

authorities in Paris and Oxford, and it was half a century before he was generally

AIBC08 22/03/2006, 11:02 AM162

philosophy in the thirteenth century

163

regarded as theologically sound. Even after his canonization in 1323 he did not

enjoy, even within his own Order, the special prestige assigned to him by Cath-

olics in recent times. In the nineteenth century Pope Leo XIII, in an encyclical

letter, gave him ofﬁcial status as the foremost theologian of the Church, and in

the twentieth century Pope Pius X gave a similar accolade to his philosophy. This

ecclesiastical endorsement harmed rather than helped Aquinas’ reputation outside

the Catholic Church, but at the present time his extraordinary gifts are gradually

being rediscovered by secular philosophers.

AIBC08 22/03/2006, 11:02 AM163