The declaration of the present Proposition will consist in a development of the earlier clauses contained in the first paragraph of

accedat ad similitudinem Dei, qui est ipsum suum esse simplex, necesse est quod forma nihil sit aliud quam divina similitudo participata in rebus. Unde convenienter Aristoteles, de forma loquens, dicit quod est divinum quoddam et appetibile.' (õvтos yáρ TIVOS Belov Kai ảyaboû kaì ¿peroù; Physic. L. i, c. 9, v. m.) 'Similitudo autem, ad unum simplex considerata, diversificari non potest, nisi secundum quod magis et minus similitudo est propinqua vel remota. Quanto autem aliquid propinquius ad divinam similitudinem accedit, (tanto) perfectius est. Unde in formis differentia esse non potest nisi per hoc quod una perfectior existit quam alia; propter quod Aristoteles (Metaphys. 81) definitiones, per quas naturae rerum et formae signantur, assimilat numeris, in quibus species variantur per additionem vel subtractionem unitatis; ut ex hoc detur intelligi quod formarum diversitas diversum gradum perfectionis requirit. Et hoc evidenter apparet naturas rerum speculanti. Inveniet enim, si quis diligenter consideret, gradatim rerum diversitatem compleri. Nam supra inanimata corpora inveniet plantas, et super has irrationabilia animalia, et super haec intellectuales sub. stantias. Et in singulis horum inveniet diversitatem, secundum quod quaedam sunt aliis perfectiora; intantum quod ea quae sunt suprema inferioris generis videntur propinqua superiori generi, et e converso; sicut animalia immobilia sunt similia plantis. Unde et Dionysius (de Divin. Nomin. c. 7) ait quod divina sapientia conjungit fines primorum principiis secundorum. Unde patet quod rerum diversitas exigit quod non sint omnia aequalia, sed sit ordo in rebus et gradus.

'Ex diversitate autem formarum, secundum quas rerum species diversificantur, sequitur et operationum differentia. Cum enim unumquodque agat secundum quod est actu, (quae enim sunt in potentia, secundum quod hujusmodi inveniuntur actionis expertia); est autem unumquodque ens actu per formam; oportet quod operatio rei sequatur formam ipsius. Oportet ergo quod, si sint diversae formae, habeant diversas operationes. Quia vero per propriam actionem res quaelibet ad proprium finem pertingit, necesse est et proprios fines diversificari in rebus, quamvis sit finis ultimus omnibus communis.

'Sequitur etiam ex diversitate formarum diversa habitudo materiae ad res. Cum enim formae diversae sint secundum quod quaedam sunt aliis perfectiores, sunt inter eas aliquae intantum perfectae quod sunt per se subsistentes, et perfecte, ad nihil indigentes materiae fulcimento; quaedam vero per se perfecte subsistere non possunt, sed materiam pro fundamento requirunt, ut sic illud quod subsistit non sit forma tantum nec materia tantum, quae per se non est ens actu, sed compositum ex utroque' (utraque?) 'non autem possent materia et forma ad aliquid unum constituendum convenire, nisi esset aliqua proportio inter ea. Si autem proportionata oportet ea esse,

1 ὅ τε γὰρ ὁρισμὸς ἀριθμός τις (διαιρετός τε γὰρ καὶ εἰς ἀδιαίρετα· οὐ γὰρ ἄπειροι οἱ λόγοι· καὶ ὁ ἀριθμὸς δὲ τοιοῦτος). καὶ ὥσπερ οὐδ ̓ ἀπ' ἀριθμοῦ ἀφαιρεθέντος τινὸς ἢ προστεθέντος, ἐξ ὧν ὁ ἀριθμός ἐστιν, οὐκέτι ὁ αὐτὸς ἀριθμός ἐστιν ἀλλ ̓ ἕτερος, κἂν τοὐλάχιστον ἀφαιρεθῇ ἡ προστεθῇ, οὕτως οὐδὲ ὁ ὁρισμὸς οὐδὲ τὸ τί ἦν εἶναι οὐκέτι ἔσται, ἀφαιρεθέντος TIVÒS TроσTE ÉVTOS. Metaph. L. viii (H), c. 3, v. f.

For definition, too, is a sort of number, (for it is divisible at once and into indivisibles, since definitions are not infinite; and number is of a similar nature). As, then, if you take away from a number any one of the elements of which the number is composed or add aught thereto, it is no longer the same, but a different number, even though the smallest subtraction or addition be made; so, in like manner, neither the definition nor the essence will remain any longer, if any subtraction or addition is made.'

this quotation from the Angelic Doctor. First of all, taking for granted that the purpose of the Creator and, consequently, the final cause of the creation is to manifest, so far as possible, the Goodness, or Perfection, (for these are really one and the same), of the Creator; it is certain,-nay, self-evident, that it would be impossible to accomplish such a design in any wise by the creation of a single individual or of a single species. It is impossible, because it involves a contradiction in terms. It is a contradiction in terms; because it supposes that any one finite being is capable of approximately representing the Infinite. It may perhaps be objected, that a similar contradiction is involved in the supposition that any number of finite beings, however multiplied, can approximately represent the Infinite. But the slightest consideration will suffice to show that the objection is not a very weighty one. It is undeniably true that neither the one nor the other can adequately represent Infinite Reality; but, if it is question of an approximative representation, no one can doubt but that a multiplication of specifically and individually distinct finite realities will more nearly approach, as types, the Infinite Reality than merely one or two specific natures, because more of reality is exhibited. The more you prolong a line, the nearer it gets to the representation of an infinite prolongation. The greater the number of distinct photographs we have of a neighbourhood or of some cathedral that we have not seen; the more complete will be our imagination of either. So also, the more extensive our observation of a man's actions and words under a variety of circumstances; the more likely is it caeteris paribus that our judgment of his character will be correct.

necesse est quod diversis formis diversae materiae respondeant. Unde fit, ut quaedam forma requirat materiam simplicem, quaedam vero materiam compositam; et, secundum diversas formas diversam partium compositionem oportet esse congruentem ad speciem formae et operationem ipsius.

'Ex diversa autem habitudine ad materiam sequitur diversitas agentium et patientium. Cum enim agat unumquodque ratione formae, patiatur vero et moveatur ratione materiae, oportet quod illa quorum formae sunt perfectiores et minus materiales agant in illa quae sunt magis materialia et quorum formae sunt imperfectiores.

Ex diversitate autem formarum et materiarum et agentium sequitur diversitas proprietatum et accidentium. Cum enim substantia sit causa accidentis, sicut perfectum imperfecti; oportet quod ex diversis principiis substantialibus diversa accidentia propria consequantur.

Rursus, cum ex diversis agentibus sint diversae impressiones in patientibus, oportet quod, secundum diversa agentia, diversa sint accidentia quae ab agentibus imprimuntur.' Cg. L. iii, co 97.

Wherefore, in order that an approximative representation of the Divine Goodness might be made, which should be as complete as the respective natures of the Architype and types would permit ; it was necessary that there should be specific diversities and individual varieties in created things. For He Who is Himself Infinite Essence can only be represented by finite being in parts, as it were, all which are eminently contained in His own Simplest Unity. Therefore, by how much these so-called parts are multiplied in the likeness; by so much does the likeness approximate to the Original. But the multiplication of these so-called parts amounts to nothing more or less than the multiplication of specific natures and individual variations. The process may be in some measure illustrated by that physical toy,—the chromotrope,—which consists of a circular disk on which have been represented in due order the prismatic colours. The disk is made to revolve with great velocity; and thus succeeds in offering to the eye a faint representation of white light. But one colour would not satisfy for the experiment.

An exception, however, may be taken to the above declaration, which merits consideration. It is universally admitted by the Scholastic Doctors, that superior Forms virtually or eminently include the inferior; for instance, the human soul virtually and preeminently contains the respective Forms of plant and animal. Why, then, should not one being of the highest finite excellence have been created, who would by virtual inclusion in his own nature represent all the reality actually represented by how many soever inferior Forms? Let the following suffice for a solution of the difficulty. (1) In such wise the fecundity of God would not be so explicitly represented. (2) Since the manifestation of the Divine likeness has been made for the sake of the intelligent creature, such manifestation will be evidently more complete, the more explicit it is. But Forms and faculties which are only eminently contained in any given entity could scarcely be known, save by comparison with other entities wherein the same faculties and Forms are explicitly revealed. What could we know of matter, of vegetative or animal life, from contemplation of an angel? (3) The Unity of the Creator is approximately represented in the creation by the perfectness of its order. But order is more admirable and is exhibited in greater perfection, proportionally to the multiplicity of beings comprised within it.

NOTE.

The above argument embraces other beings than those which constitute the material universe, and will be extended to pure Intelligences in another place. Its present restriction is consonant with the subject-matter of this and the preceding Chapter.

PROPOSITION CLXXXVII.

The specific diversity to be found in material substances is essentially due to the respective substantial Forms which determine the specific nature of the composites.

DECLARATION OF THE PROPOSITION.

The present Thesis does not include the question of individual variations. The inquiry is confined for the moment to specific differences. It should further be borne in mind, that the term, species, is here used in a strictly metaphysical sense, as identified with the integral essence of a thing. Now, that which constitutes or determines the essential nature of an entity must be something intrinsic; for we are not dealing at present with efficient causality. Furthermore: This something intrinsic determinative of the essential nature must be either the matter or the Form; for these are the only two substantial constituents of a body. But it cannot be the matter which is common to all bodies. It must, therefore, be the substantial Form. Hence, Aristotle describes it, as we have seen, to be something Godlike, and good, and desirable'; and the Angelic Doctor explicitly asserts, in the concluding sentence of the first paragraph, that 'entities are diverse by reason of their having a diversity of Forms from which they acquire their specific nature.' It is unnecessary to prolong the declaration; since the whole of the present Chapter is one continuous elucidation of its truth.

COROLLARY I.

That which the substantial Form, metaphysically considered, does for the specific nature and diversity of material substances, this same Form physically and in the concrete does for the individual nature and individual variations. In the former way of conceiving it, it is regarded as the essential rather than the existing Form; in the latter, as the existing rather than the essential

Form. Considered adequately, it is that which constitutes this individual nature in its existing specific essence.

COROLLARY II.

From the truth of the present Proposition it follows that all classification of material substances should be based on the substantial Forms, not on varieties of structure, colour, or other accidents only or even principally. How this can be done, since these Forms are not subject to the perception of sense, will be seen more clearly in the sequel.

Without venturing to cast a doubt on the practical usefulness of the classifications adopted by modern physicists in their respective departments, (since, for all the present writer knows, they may be the only ones which an exclusive study of physical phenomena would enable these authorities to use with safety and advantage); it may safely be permitted to question the acknowledged principles of these arrangements, which indeed must be defective, if the Proposition just declared is true. In Zoology more particularly, these principles for the most part resolve themselves into two main points, viz. specialization of function and morphological type,-to borrow the peculiar nomenclature of the day. Now, both immediately and formally belong to the material cause and its accidental organization, the latter evidently, since it embraces what are supposed to be the fundamental points of structure; the former likewise, because it does not fasten on the operation or function itself so much, as the organic apparatus by which the function is carried out. But each of these is an effect at the best, not a cause, of specific difference; and cannot of itself be a safe guide in determining a really scientific arrangement. To this must be attributed the acknowledged uncertainty and frequent changes in our modern. systems of classification. To take a striking instance:-The Mammalia are certainly not an unimportant Division among the Vertebrates or highest order of animals. Yet Dr. Nicholson informs us, that Numerous classifications of the Mammalia have been proposed, and it is a matter of regret that no one has been universally accepted by zoologists'.' He contents himself with enumerating three; the first of which is determined by a vascular organ,—the placenta,-developed during the period of gestation. The second is based on certain

1 Manual of Zoology, Ch. lxxiii, init., p. 484.