Western Philosophy. Группа авторов
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Название: Western Philosophy
Автор: Группа авторов
Издательство: John Wiley & Sons Limited
Жанр: Афоризмы и цитаты
isbn: 9781119165743
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1 1 ‘In a subject’: in the sentence ‘Socrates is bald’, the attribute of baldness is in the subject (Socrates). ‘Said of a subject’: in the sentence ‘Socrates is a man’, what is said of Socrates is the species to which he belongs. Aristotle is about to argue that the individual subject (e.g. Socrates) is the basic or primary substance. Species and genus (e.g. man, animal) are substances only in a secondary sense, since they would not exist at all if individuals did not exist.
3 Supreme Being and Created Things: René Descartes, Principles of Philosophy*
The notion of a substance played a key role in the metaphysical thought of the Middle Ages. As we have seen, Aristotle conceived of a substance as an individual subject enduring through change, and having independent existence. In the thirteenth century, the celebrated philosopher and theologian St Thomas Aquinas, taking his cue from Aristotle, defined a substance as an ens per se existens – an ‘entity existing through itself’ (independently, or in its own right).1 But if the idea of an independent being is construed in the strongest possible sense, as something whose existence is entirely self-sufficient, then one might conclude that the term ‘substance’ should strictly speaking be reserved for God alone (since, according to standard Christian doctrine, He alone is the eternal source of all being, and the existence of everything else is dependent on Him). And this is precisely the line taken several centuries later by René Descartes, at the start of the following extract from the Principles of Philosophy (Principia Philosophiae, published in Latin in 1644).
God, according to Descartes, is the sole substance in the strict sense; created things can count as substances only in a secondary sense. But in his account of created things, Descartes makes a striking departure from the framework for understanding reality which Aristotle had offered. The Cartesian2 framework for explaining the physical world offers a radically new ‘ontology’ – a radically new conception of what there is. As we saw in the previous extract, Aristotle grouped individual substances together as belonging to natural kinds (species and genera); and among ‘scholastic’ medieval philosophers (those who followed a broadly Aristotelian approach), a great deal of energy was spent in classifying natural phenomena, and explaining the way things behaved in terms of the essential characteristics of the natural kind to which they were taken to belong. (The traditional classificatory scheme involved four principal elements, earth, water, air and fire, each made up of different combinations of the four qualities, Cold, Wet, Dry and Hot.) Ushering in the scientific revolution of the seventeenth century, Descartes argues that to understand natural phenomena we need instead to adopt a mathematical approach. What matters for explanation in physics are not differences in ‘kind’ but a quantitative analysis, expressible in terms of strict mathematical laws. Hence we find, in place of the traditional plurality of individual substances belonging to various natural kinds, just one essential kind of matter: the whole universe is composed of a single ‘extended stuff’, and all phenomena are to be explained quantitatively, in terms of the size, shape and motion of its particles.
Descartes’s account of the world thus conceives of matter as a single extended body, indefinitely modifiable as to its dimensions, and dependent only on the supreme substance, God, for its existence and the movement of its parts. Finally, to complete the picture, there are, in addition to the creator and the physical world, created minds or souls: individual centres of consciousness, whose existence, Descartes maintains, does not require anything material (for more on this notion of the immaterial mind, compare Part IV, extract 4, below). Descartes’s ontology thus gives us three categories of substance: first, substance in the strict sense – the independent, self-sufficient creator, God; second, extended substance, or matter; and third ‘thinking substance’ – the category to which created minds belong.
What is meant by ‘substance’ – a term which does not apply univocally to God and his creatures.
In the case of those items which we regard as things or modes of things, it is worthwhile examining each of them separately. By substance we can understand nothing other than a thing which exists in such a way as to depend on no other thing for its existence. And there is only one substance which can be understood to depend on no other thing whatsoever, namely God. In the case of all other substances, we perceive that they can exist only with the help of God’s concurrence. Hence the term ‘substance’ does not apply univocally, as they say in the Schools, to God and to other things; that is, there is no distinctly intelligible meaning of the term which is common to God and his creatures. In the case of created things, some are of such a nature that they cannot exist without other things, while some need only the ordinary concurrence of God in order to exist.3 We make this distinction by calling the latter ‘substances’ and the former ‘qualities’ or ‘attributes’ of those substances.
The term ‘substance’ applies univocally to mind and to body. How a substance itself is known.
But as for corporeal substance and mind (or created thinking substance), these can be understood to fall under this common concept: things that need only the concurrence of God in order to exist. However, we cannot initially become aware of a substance merely through its being an existing thing, since this alone does not of itself have any effect on us. We can, however, easily come to know a substance by one of its attributes, in virtue of the common notion that nothingness possesses no attributes, that is to say, no properties or qualities. Thus, if we perceive the presence of some attribute, we can infer that there must also be present an existing thing or substance to which it may be attributed.
To each substance there belongs one principal attribute; in the case of mind, this is thought, and in the case of body it is extension.
A substance may indeed be known through any attribute at all; but each substance has one principal property which constitutes its nature and essence, and to which all its other properties are referred. Thus extension in length, breadth and depth constitutes the nature of corporeal substance; and thought constitutes the nature of thinking substance. Everything else which can be attributed to body presupposes extension, and is merely a mode of an extended thing; and similarly, whatever we find in the mind is simply one of the various modes of thinking. For example, shape is unintelligible except in an extended thing; and motion is unintelligible except as motion in an extended space; while imagination, sensation and will are intelligible only in a thinking thing. By contrast, it is possible to understand extension without shape or movement, and thought without imagination or sensation, and so on; and this is quite clear to anyone who gives the matter his attention.
How we can have clear and distinct notions of thinking substance and of corporeal substance, and also of God.
Thus we can easily have two clear and distinct notions or ideas, one of created thinking substance, and the other of corporeal substance, provided we are careful to distinguish all the attributes of thought from the attributes of extension. We can also have a clear and distinct idea of uncreated and independent thinking substance, that is of God. Here we must simply avoid supposing that the idea adequately represents everything which is to be found in God; and we must not invent any additional features, but concentrate only on what is really contained in the idea and on what we clearly perceive to belong to the nature of a supremely perfect being. And certainly no one can deny that we possess such an idea of God, unless he reckons that there is absolutely no knowledge of God to be found in the minds of men …
How thought and extension may be distinctly recognized as constituting the nature of mind and of body.
Thought and extension can СКАЧАТЬ