Practical philosophy

Mathematics

Mathematics was recognized by Aristotle as a division of philosophy, co-ordinate with physics and metaphysics, and is defined as the science of immovable being. That is to say, it treats of quantitative being, and does not, like physics, confine its attention to being endowed with motion.

Practical philosophy

This includes ethics and politics. The starting-point of ethical inquiry is the question: In what does happiness consist? Aristotle answers that man's happiness is determined by the end or purpose of his existence, or in other words, that hishappiness consists in the "good proper to his rational nature". For man's prerogative is reason. His happiness, therefore, must consist in living conformably to reason, that is, in living a life of virtue. Virtue is the perfection of reason, and is naturallytwofold, according as we consider reason in relation to the lower powers (moralvirtue) or in relation to itself (intellectual, or theoretical, virtue). Moral virtue isdefined "a certain habit of the faculty of choice, consisting in a mean suitable to ournature and fixed by reason, in the manner in which prudent men would fix it". It is of the nature of moral virtues, therefore, to avoid all excess as well as defect; bashfulness, for example, is as much opposed to the virtue of modesty as shamelessness is. The intellectual virtues (understanding, science, wisdom, art, and practical wisdom) are perfections of reason itself, without relation to the lowerfaculties. It is a peculiarity of Aristotle's ethical system that he places theintellectual virtues above the moral, the theoretical above the practical, thecontemplative above the active, the dianœtical above the ethical. An important constituent of happiness, according to Aristotle, is friendship, the bond between theindividual and the social aggregation, between man and the State. Man isessentially, or by nature, a "social animal", that is to say, he cannot attain completehappiness except in social and political dependence on his fellow man. This is the starting point of political science. That the State is not absolute, as Plato taught, that there is no ideal State, but that our knowledge of political organization is to be acquired by studying and comparing different constitutions of States, that the best form of government is that which best suits the character of the people--these are some of the most characteristic of Aristotle's political doctrines.

Poetical philosophy

Under this head came Aristotle's theory of art and his analysis of the beautiful. When Aristotle defines the purpose of art to be "the imitation of nature" he does not mean that the plastic arts and poetry should merely copy natural productions; his meaning is that as nature embodies the idea so also does art, but in a higher and more perfect form. Hence his famous saying that poetry is "more philosophical and elevated than history". Hence his equally famous doctrine that the aim of art is the calming, purifying (katharsis) and ennobling of the affections. For this reason, he prefers music to the plastic arts because it possesses a higher ethical value.
Aristotle's conception of beauty is vague and undefined. At one time he enumerates order, symmetry, and limitation, at another time merely order and grandeur, as constituents of the beautiful. These latter qualities he finds especially in moralbeauty. It is impossible here to give an estimate of Aristotle's philosophy as a whole or to trace its influence on subsequent philosophical systems. Suffice it to say that, taken as a system of knowledge, it is scientific rather than metaphysical; its starting-point is observation rather than intuition; and its aim, to find the ultimatecause of things rather than to determine the value (ethical or æsthetic) of things. Its influence extended, and still extends, beyond the realms of science andphilosophy. Our thoughts, even on subjects far removed from science andphilosophy, fall naturally into the Categories and formulas of Aristoteleanism, and often find expression in terms which Aristotle invented, so that "the half-understood words of Aristotle have become laws of thought to other ages".