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“In reading great literature I become a thousand men and yet remain myself… Here, as in worship, in love, in moral action, and in knowing, I transcend myself: and am never more myself than when I do.”

C S Lewis[1]

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What is knowledge?  How is it that we know?  How is it that we grasp—that we take in, so that it becomes something within—what is outside us, in such fashion that we are able to use it to develop and enlarge ourselves?

The Natural Compound

Every material thing is composed of prime matter and substantial form.  The manner in which matter and form are united in such a compound has three characteristics.  First, the matter appropriates the form subjectively; it limits it to itself.  When water receives the form ‘heat’, that heat becomes the heat of the water, and is limited to the water.  When wax receives the form ‘spherical’, the sphericality is that of the wax; it is limited to the wax.

Secondly, the matter receives the form physically.  Physical change takes place in it.  The matter is now determined in a fashion physically different to that it previously had, and its previous form is necessarily corrupted.  When matter receives the form of water, the matter becomes physically water and the forms of oxygen and of hydrogen previously had are corrupted.  When water receives the form of heat it becomes physically hot, its previous form (of coldness) is corrupted.  When the wax receives the form of sphericality, its previous form (cubeness?) is corrupted.

Thirdly, the matter receives the form compositively.  There is a mutual tampering between matter and form which produces this third, the compound.  So, water is not merely matter, and not merely the form of water, but a compound of the two.  The compound hot water is something which is not simply heat, or simply water, but the compound hot-water; and spherical wax is not simply wax or sphericality but the compound, spherical-wax.

The Intentional Compound

St Thomas teaches—

“Knowers are distinguished from non-knowers in this, that non-knowers have nothing save their own form only; but a knower is naturally apt to have the form also of another thing; for the species (ie, the form) of the known is in the knower.”[2]

Between living things which are automotive as regards execution only (plants) and living things which are automotive also as regards form (brute animals, and rational animals), there is a radical difference.  The latter, while retaining their own proper form, have the power to take in the forms of other things.  How? “[Cognoscere est] habere aliquid in se formaliter et non materialiter.”[3]  To know is to have something in self formally and not materially.  That is, the knower grasps the form of the external thing without its conjoined matter, without the need to be united to it subjectively, physically and compositively.  To know, then, is to exercise a power of receiving the forms of other things but not in the way they are received in nature.  In other words, the knower has the forms of the things it knows immaterially.

But a distinction must be drawn between the respective manners of knowing of brute animals and rational animals (men).  Here is St Thomas again.

“[P]lants, and those things which are below plants can receive nothing immaterially; and therefore they are bereft of all knowledge… [S]ense receives form without matter, but nevertheless with material conditions.  But intellect receives forms purified also from material conditions.[4]

At the level of sense

“Sense is receptive of forms without matter as wax receives the seal of the ring without the iron and the gold…  [S]ometimes a form is received in a patient according to another manner of be [esse] than it has in the agent because the material disposition of the patient to receive is dissimilar to the material disposition in the agent.  And then the form is received in the patient without matter [because] the patient is assimilated to the agent according to form and not according to matter.  And this is the manner… in which sense receives form because form has be [esse] in one manner in sense, but in another manner in the thing sensed.  For in the thing sensed it has natural be [esse naturale] but in sense it has intentional and spiritual be [esse intentionale et spirituale].”[5]

St Thomas is not here attributing spiritual powers to the sense knower but highlighting the fact that in its sensed activities the animal (whether brute or rational) acts in a manner above the merely material, a manner which is objectively immaterial[6].  But the rational animal—the one possessed of intellect [man]—not only acts at a level which is objectively immaterial but also subjectively immaterial.  For he is himself essentially immaterial.[7]

At the intellectual level

The form known via the senses is always this form, singular and individual.  The senses detect this whiteness in a cloud, or this circularity in the orb of the moon, or this heat in the fire.  Man shares with the brute animal this power of sense knowledge.  But there is another way of knowing unique to man which involves a further level of abstraction of which the brute animal is incapable.  In this higher manner of knowing, he abstracts from ‘this-ness’.  He considers the form not as singular, but as universal, applicable to many individuals.  Thus he deals with—

  • whiteness itself, abstracted from cloud, or milk, or the petals of a rose;
  • circularity itself, abstracted from full moon, or the sun, or a geometrical figure drawn on paper with a compass;
  • heat itself, abstracted from fire, or volcano, or the sun.

St Thomas describes this higher manner of knowing—

“Sense… receives the form of sensibles without the matter, as for instance the colour of gold without the gold… Intellect receives the species (forms) of bodies which are material and movable according to its own manner, immaterially and immovably.”[8]

In the commentary on Aristotle’s De Anima he considers the question why sense is of singulars but intellect (which produces science) is of universals.  He says—

“[S]ense is a power in a corporeal organ, but intellect is not an act of such an organ; it is an immaterial power.  Now whatever is received, is received after the manner of the recipient.  But knowledge occurs through this, that the known is in some manner (that is, according to its similitude) in the knower.  For the knower in act is the very known in act.  Therefore it must needs be that sense receives the similitude of the thing it senses, corporeally and materially, whereas intellect receives the similitude of what it understands, incorporeally and immaterially.  But the individuation of a common nature in corporeal and material things is from corporeal matter contained under determinate dimensions.  But the universal is through abstraction from such matter and from individuating material conditions.  Hence it is manifest that the similitude of a thing received in sense represents the thing according as it is singular; but (the similitude) received in intellect, represents the thing according to the essential character of [its] universal nature.  Hence it is that sense knows singulars, but intellect knows universals, and science is of universals.”[9]

The Value of our Knowledge

Through knowledge a living thing is given a remedy, so to speak, for the limitations and poverty of its own being.  St Thomas again:

“A thing is perfect in two ways.  First, according to the perfection of its own act of existence [esse] which pertains to it according to its proper species… [But] the perfection of each thing considered in itself is imperfect [since it is but] part of the perfection of the whole universe… Therefore, that there be some remedy for this imperfection, there is another mode of perfection in created things, according as the perfection proper to one thing is found in another: this is the perfection of a knower inasmuch as it knows.  Because according as something is known by a knower, the very known is in some way within the knower.  And therefore it is said in the Third book of the De Anima that the soul is in a certain manner all things, because it is naturally apt to know all things.  And in this way it is possible that in one thing there should exist the perfection of the whole universe...”[10]

How blessed is mankind to have been given the gift of knowledge!  What thankfulness ought we not show each day of our lives for this great gift to the Author of our being.

Michael Baker
21st August 2007—St Pius X

[1]  An Experiment in Criticism, 1961, quoted in Barbara Reynolds, Dorothy L. Sayers: Her Life and Soul, Hodder & Stoughton, London, 1993, p. 193.

[2]  St Thomas Aquinas, Summa Theologiae, I, q. 14, a. 1

[3]   St Thomas Aquinas, In Librum de Causis, lect. 18

[4]  Questiones Disputatae de Veritate, q.2, a. 2; and cf. a. 3.

[5]  In II De Anima, lect. 24

[6]  Not because of any inherent immateriality in the animal, but because it is endowed by its Author with a power—the power of sensation—of extracting the forms of things without their conjoined matter.

[7]  This is not to deny that man has a body; it is to insist that his soul, the form according to which he both lives and exists, is not material but spiritual.  His body, the material part of him, exists to serve his soul, the immaterial part of him, though the two form an essential unity.

[8]  Summa Theologiae, I, q. 84, a. 1.

[9]  In II De Anima, lect. 12

[10]  Questiones Disputatae de Veritate, q.2, a. 2; the reference is to Aristotle’s work De Anima, III, c. 8.