Various names have been assigned to this science. It would appear that it was originally called Wisdom; till Pythagoras, impressed with the conviction that the mind of man could but scantly measure its length and breadth and height and depth, termed it, modestly enough, Philosophy or the love of Wisdom, and those who dedicated themselves to such investigations, Philosophers or lovers of Wisdom. Nevertheless, it must not be supposed that these titles of Wisdom and Philosophy were exclusively reserved for Metaphysics; since they were occasionally applied to other branches of study. Whosoever in their generation had a reputation among their fellows for superior knowledge, let the particular line of knowledge pursued by them have been what it might, were frequently designated by common consent Wise men and Philosophers. Somewhat similar to this is the use of these words in our own day. We hear and read of mental philosophy, of moral philosophy, of the philosophy of history, of natural philosophy. Nay more, the words philosophy, philosopher, like those of science and scientific men, are, not too modestly, restricted by modern physicists to a study of natural phenomena and to those who, like themselves, have made these phenomena their exclusive study.
Aristotle graces Metaphysics with manifold appellatives of honour. He calls it wisdom, the philosophy, the first philosophy, the first science, the Divine science, the science of sciences, the Queen of sciences. The series of treatises which he has written on this subject received, subsequently to his time, in their collected form the name of Metaphysics (meta ta phusika); though the phrase occurs more than once in his own writings. It seems hardly necessary to remind the reader that the Greek preposition cannot be understood to express (as some have understood it){1} an elevation above the things of nature. Its only admissible rendering in the present instance is, after; and consequently the phrase should be translated, after physics. Let it not, however, be thence imagined that this same after denotes the rank or position of metaphysics in the family of sciences, as though the first science were subordinate to physics; for such an interpretation would contradict the invariable teaching of the Philosopher. It merely means that the former comes after the latter in order of analysis and, more particularly, in the curriculum of studies. We naturally begin with objects which are pervious to, and thence go on to those which are beyond and above, sensile perception. He would be ill prepared for the contemplation of ontological truth and for an investigation of the abstract and difficult questions which it involves, whose mind has not been previously disciplined by a course in physics, and especially in mathematics. Such is the interpretation given of this phrase by the Angelic Doctor. 'The science,' he remarks, 'which treats of all these subjects' (i.e. of God, Angels, Substance, Quality, Faculty, Act, &c.) 'is Theology, i.e. the Divine science, so called, because in it God is the primary Object of cognition. It has also received the name of Metaphysics, i.e. beyond physics, because to us, who naturally arrive at the knowledge of things immaterial by means of things sensible, it offers itself by rights as an object of study after physics. It is also called the First Philosophy; because other sciences receive their first principles from it, and are, therefore, secondary to it.'{2}
In more recent times it has been not unusual to call this science Ontology, or the science of Being. Some moderns have likewise styled it General Metaphysics, to distinguish it from what they designate as Special Metaphysics. This latter is identical with those sciences which among the ancients and in the School were known by the name of Natural Philosophy, a term now commonly adopted to express the sum of physical discoveries. It is probable that the new nomenclature of General and Special Metaphysics was, in great measure, suggested by a desire to avoid the inevitable confusion which must otherwise have resulted from this change in the meaning of Natural Philosophy; but those names are liable to serious objection, as tending to subvert the true limits of metaphysical investigation.
Hegel, in consonance with his theory of the ideal Absolute, identifies Metaphysics with Logic. His Logic, however, is not the science of the forms of thought or Second Intentions, as commonly understood; but is, -- to borrow his own phrase, -- 'the Science of the pure Idea.'
When the titles of Wisdom, Theology, the Divine Science, the First Philosophy, and the like, are claimed for Metaphysics; it must be understood that such presidency affects those sciences only which are acquired by pure process of the natural reason. The science of supernatural Theology, supposing of course that there is such a science, must from the very nature of the case be paramount. But it is equally plain, that supernatural Theology is wholly distinct from the natural sciences, seeing that it belongs to another order. It may have, it is true, its legitimate authority and power of direction even within the sphere of Metaphysics; but such authority will be indirect, negative, and external to all scientific process of development. The two sciences are in themselves essentially distinct; for whereas the first premisses of supernatural Theology are objects of faith, those of Metaphysics, as of the other natural sciences, are subject to the intuition of the understanding. The former rely for their acceptance on extrinsic; the latter, on intrinsic evidence. Hence, in supernatural Theology, authority holds the foremost place, while in the natural sciences it goes for next to nothing; for in the former the authority is Divine and is the formal motive of assent, but in the latter it is human and consequently insufficient for scientific cognition. Nevertheless, human authority even in Metaphysics may have a certain value, in so far as it sets before us principles of philosophy which have stood the test of time, continue to arrest the mind by the brightness of their own intrinsic evidence, and are ready to hand for the work of present construction; or, again, forasmuch as the genius of the wise and learned in past ages may serve to adjust our intellectual telescope, while we painfully strive to precise the nebulae which cross our field of view.
There is another element of distinction between supernatural Theology and the natural sciences, arising out of the nature of their respective objects. For of the former the principal object are mysteries, the adequate object a supernatural Revelation; while the object of the latter is limited to such truths as are open to the cognition of the unaided human intellect. Other differences there are which shall be omitted here, because they are not germane to the course of thought upon which we are about to enter. It cannot be denied, indeed, that supernatural Theology has incidentally led the way to great discoveries within the defined boundary of metaphysical truth. Yet even in such case human reason has only been put on the scent, so to speak, by the revealed mystery; but has pressed forward in pursuit by the strength of its own processes, and has come up with the truth, thus pointed out to it, by virtue of its own demonstrations.
Here it may be necessary to anticipate an objection which might present itself to the mind of the reader; for if it be true that Metaphysics rests on reason, not on authority, he may be puzzled to understand what purpose is to be gained by those numerous quotations which he will encounter in the present work. Let it suffice, then, to say, that they are not produced as proofs but as witnesses to proofs; while each proof must stand or fall according to the intrinsic evidence which it possesses. Their appearance is due to the fact that the author professes to present the Peripatetic philosophy before the public in an English dress. He is an interpreter rather than a philosopher; handing down the teaching of others, not professedly publishing his own. He could not, therefore, content himself with merely exhibiting that philosophy; but was bound to stamp his statements with the seal of the chief among those Doctors whose system he has undertaken to expose.
These prefatory observations introduce us to the fundamental question touching the nature and limits of Metaphysics. And, first of all, it behoves us to determine its definition. By some it has been defined to be, the science of things which either surpass matter or are separated from it by abstraction; by others, as the science of things either positively or negatively immaterial. These two definitions are substantially the same. For things positively immaterial are such as in their own nature and essence surpass and exclude matter; while the negatively immaterial are those which, though material in themselves, are considered by the intellect apart from their material conditions, and are, consequently, separated from matter by abstraction. They are both, however, generic definitions at the best; and would seem to have been adopted in conformity with the modern usage of including under Metaphysics Anthropology and Cosmology. According to the ancient and accepted definition, which is every way preferable and will therefore be retained in this work, Metaphysics is 'a science which contemplates real Being as such.'{3}
A science may be considered either subjectively or objectively. It is considered subjectively, when regarded as an accidental quality inhering in the Subject who possesses it; objectively, when it represents the objects of cognition, i.e. the hierarchy of truths with which the subjective habit is conversant. Thus, for instance, when Sir Isaac Newton is said to be a great mathematician, the science is considered subjectively; when we speak of the Differential Calculus forming a part of mathematics, it is considered objectively. Now 'there are three, and three only, requisites for science; to wit, the active faculty of the thinker by which he judges of things, the thing thought, and the union of the two;'{4} in other words, subjective intellect, an objective fact or truth, and the represention of that truth in the intellect. The proper definition of any such habit will give the subjective element in the Genus, the objective in the Differentia, and consequently the two conjoined in the entire definition. For every science is differentiated by the subject-matter of its investigation, or (which comes to the same thing) by the object of its contemplation.
According, then, to the definition already adopted, Metaphysics is subjectively a science, objectively the truths of Being as such; while in its complete and essential nature it is the science of Being, of the truths of Being, simply as such.
{1} 'Ens metaphysicum, i.e. supra naturam elevatum, ut sunt angeli et Deus.' Goudin, Philos. D. Thomae, Intr. a. I.
{2} 'De quibus omnibus est Theologia, i.e. Divina scientia, quia praecipuum cognitorum in ea est Deus. Alio nomine dicitur Metaphysica, i.e. transphysica, quia post physicam discenda occurrit nobis, quibus ex sensibilibus competit in insensibilia devenire. Dicitur etiam philosophia prima, in quantum scientiae aliae, ab ea principia sua accipientes, eam sequuntur.' Opusc. LX (aliter LXIII), in Boet. de Trinit. Q. 5, a. I, in c.
{3} Estin epistêmê tis he theorei to on he on. Arist. Metaph. L. IV (aliter III), c. I.
{4} 'Ad scientiam non requiruntur nisi tria; scilicet, potentia activa cognoscentis qua de rebus judicat, res cognita, et unio utriusque.' D. Thom. de Verit. Q. ii. a. I, b. 3.