Aristotle is famous as a pioneer in the development of the science of logic. In his blending together of the methods of induction and deduction he brings about a reconciliation between the theories of empiricism and rationalism. Know- ledge, according to Aristotle, begins with sense-perception and so logic commences with induction from the particular to the universal, but the universal is prior to the particulars in its nature though it is arrived at later by human reasoning. The whole is prior to its parts and is the purpose to be realised by the parts. The knowledge of the particulars in full requires a knowledge of the universal. Deduction is the way to the right knowledge of things but the way to deduction is induction. The universals from which we deduce the particulars are to be roused in our reason by means of sense-perception and induction. There would be no knowledge without sense-perception but the certainty of this experience is assured only when its truths are present in the reason potentially.

Aristotle's logic is a great aid in understanding his metaphysics, which he calls the first philosophy. Metaphysics is the search for Reality. Aristotle sees a transcendency in the nature of Plato's Ideas and their unrelatedness to the world of matter. He understands that there is a dualism in Plato's philosophy and tries to bridge the gulf between the Ideas or the Forms and the matter of sense-perception. The Idea or the Form cannot be independent of matter, nor can be matter without a form directing it. The objects of the world are real substances, not imperfect copies of the Platonic universal Ideas. The reality of the objects, however, is the forms, the general qualities of the genus to which they belong. The form or the Platonic Idea is in matter, not outside it; immanent, and not transcendent.

To Aristotle, the visible is changeable. Things of the world change; there is evolution but there is some element in them which persists through all change. The changing qualities are predicated of this persistent element. This principle underlying change Aristotle concludes to be matter. Matter does not change with change. It persists through all change. Matter is never without qualities and there is no such thing as formless matter in the world. There is a togetherness in the existence of matter, qualities and forms. In change the form does not change; matter puts on different qualities which is called change. We must be careful in using the word 'form' when we are studying Aristotle; for he means by form not the visible shape of an object but the Platonic Idea that underlies the shape of the object, as its shaping form, which gives it reality. When matter appears to change it is not the previous form that changes itself into another form, but a different form altogether begins to give shape to matter. Thus matter goes on changing forms. These forms, like the Purushas of the Sankhya, are ever-persistent and not newly created at any time. And, like the Sankhya, Aristotle says that matter and the forms are both eternal principles, never destroyed. Matter, the ever-persistent, which assumes different conditions in change on account of the presence of different qualities, and the forms which animate it, constitute the world. But qualities, Aristotle holds, are real existence. All things, in Aristotle, are compelled by an inner necessity to outgrow themselves and realise their purpose in a form which exists as the potential in matter. Everything is matter and form at the same time, the higher being the form of the lower and the lower the matter of the higher. There is an evolution of the higher form from the lower, which exists as the matter or potentiality of the higher. Form is the total force residing in a thing as the very essence of being, doing and becoming. There is no external mechanical cause in the unfoldment of the actuality of things but the real cause is the internal necessity which works with due reference to the type to which the things belong. When a thing develops fully it is said to have reached its form or realisation of true being; its purpose here is fulfilled. Every change in a thing is guided by a purpose and end, a goal which is the actualisation of the higher form. The potential becomes actual at every stage. Matter has a tendency, a desire or a love to realise its form, and here it co-operates with the function of the necessity directed by the great purpose which consists in the realisation of the form. Aristotle thinks that matter sometimes does not cooperate with its form, works independently and opposes the unfoldment of the form; this is offered as the reason for the differences, monstrosities and defects detectable in the world.

The process of the realisation of the purpose of the form passes through the stages of a fourfold causation; the potential form or the idea lying at the root of action which is the formal cause; the matter or the basis of action which is the material cause; the instrument or that through which the action is done, which is the efficient cause; and the purpose to be realised in action which is the final cause. When man works on a material these four causes are visible but in organic nature the instrument of action is identical with the form and the unrealised also is the form, so that only form and matter remain in the end as the only two causes. Every form is guided by a purpose towards which it moves, the realisation of the highest form of the species which are held to be unalterable. The form, like the Purusha of the Sankhya, is responsible for the teleological motion of matter. Motion is the process of the actualisation of the potential, and this motion is caused in matter by the mere presence of the form. Motion is not mechanistic, but teleological.

Now comes the crowning part of Aristotle's philosophy. The process of motion makes Aristotle posit God as the final Unmoved Mover, a logical necessity which alone can put an end to an infinite recourse in our search for a final cause of all motion. This final cause should be causeless, unmoved but moving all things. This God is eternal, Form without matter, Pure Spirit or Intelligence, for if there is matter in God, He would be subject to motion. God is the Supreme Purpose of all things. The world longs for God whose presence is the cause of all motion. The desire to realise Him is implied in the desire to realise one's essential being, viz., the form. The God of Aristotle is in some respects like the God of Hegel who is the Absolute Reality, the being which is the meaning, purpose and value of the whole universe. But in another sense Aristotle's God is different from Hegel's, for the former has no need for matter, while the latter needs the world. The God of Aristotle is free from all psychological functions known to man; He has perfect intelligence whose action consists in mere Being and Knowing. He is Omniscient and His knowledge is complete, non-rational, immediate, and not a successive process. He is the Goal of life. God, the Unmoved, moves the world not as an external agent, but as 'the beloved moves the lover', a welling sum of force that moves the totality of being by its very existence. Grand philosophy of Aristotle! The saying that all men are born either Platonists or Aristotelians is not without some truth.

Sometimes Aristotle's form looks like the Idea of Plato and at other times like the Elan Vital of Bergson. The forms of Aristotle are many. They are only changed in the change which matter assumes, as if there is a jump from one form to another, with an unbridged gulf between the two forms. The view that in the changes assumed by matter different unrelated forms begin to inform it is untenable, for then matter would find no link to connect itself with the next higher form. And yet Aristotle makes the higher form evolve out of the lower in which it exists potentially. It follows from this that the higher form is latent in all the lower ones, and God the Highest Form is in everything hidden as the unrealised actual. This shows that there ought to be, really, only one Form, namely God, which is gradually unfolded and actualised in evolution, and not many forms which seem to have no relation to each other. Aristotle's forms are the different degrees in which the Supreme Form, or God, is revealed in gradual realisation by the process of evolution. The use of the plural viz., forms, in regard to the degrees of the revelation of the sole reality of the Supreme Form would create a confusion in the minds of students. But if Aristotle really means that there is a plurality of forms, his metaphysics cannot avoid the defect of discrepancy and the charge of holding contradictory and untenable positions. In the philosophy of the Vedanta, there is only one reality, the Absolute, and all the multifarious souls of the world are appearances of the one Absolute in different individual constitutions, even as the one Sun appears as if many when reflected in the waters contained in many vessels. Matter, in the Vedanta, does not leap from one form to another form but gets more and more transparent and extended in the higher evolution on account of its allowing thereby the manifestation of the consciousness of the Absolute in ever-widening and intensified degrees.

When Aristotle says that every form has its purpose in the realisation of the highest form of its species and that such species are unchangeable, he makes one feel that there are different forms for different species, another confusion caused by the notion of the plurality of forms, which, if they are really plural, would stultify the very meaning of God as the Supreme Form, for reasons already mentioned. The species also should, in the end, be stages in the development of the Form of God, if God is to be accepted at all as the ultimate Form. In the Vedanta, we do not find the attribution of different forms to species, for species too are just rungs in the unfoldment of consciousness in the process of the realisation of the Absolute. No independent reality can be given to the different species or genera. Nothing diversified or discrete in nature can enjoy true independence or freedom. All are stages in Self-realisation.

Aristotle thinks that a human soul cannot inhabit an animal body. There is only ascendance in organic life to higher forms. There seem to be several souls beginning from the lowest undeveloped organism to the fully developed human being. According to the Vedanta, there is a possibility of the human soul's reverting to a lower order of life due to the perpetration of an evil action, though, when the result of this action is fully experienced in this lower life, the human soul rises once again to its original condition even if it has to pass through several orders of the lower species due to its binding actions. The human soul can lie latent even in inorganic matter; it all depends upon the kind of action one does. Retributive justice compels the human being to experience the fruits of his actions whether it be in a super-human state or a sub-human one. It is the materialisation of the force of action that the soul is compelled to experience and this necessity has no concern whatsoever with the state or the species in which this experience may have to be undergone by the human soul.

There is a complaint from many a man in the street today that the seeking for personal salvation is selfish, that individual salvation is not the goal aimed at by the really great compassionate men. Aristotle makes it clear that personal or individual immortality is inconceivable. The essential or the creative reason in man is universal; it is the divine being that manifests itself in man as the higher creative reason, and not a personal faculty confined to any particular individuality. This essential reason may be identified with the Supreme Being, God. Hence the attainment of the immortal is one's being universal and not gaining a personal or selfish end. To Aristotle Self-realisation is the fulfilment of the universal purpose, the realisation of the true good of all beings. Aristotle insists that it is the foremost duty of every rational human being to stick to the immortal at any cost, that the philosophical pursuit is an imperative, and that the highest activity of man consists in the contemplation of the Real. We have in Plato and Aristotle the perfect specimen of a true philosopher. They are sometimes inclined, of course, to emphasise the social and political side of life as the end of human existence, which attitude has to be attributed to the condition of the times in which they lived, rather than to their fundamental inclinations or natural temperaments. They were philosophers of the society and the State, whose perfection and strength were considered to be indispensable for the evolution of the individual towards the realisation of the Divine Being.