140. Habits and Morality.--The importance of habits in man’s moral life is very great. (a) Habits are an index to a man’s past career, for the ease and facility he now possesses through them is the result of many struggles and efforts and difficulties overcome, or of defeats and surrenders and neglected opportunities. (b) Habits constitute a man’s moral character. Morally, a person is the sum of his moral habits and dispositions grouped around the central interest or idea of his life. He who would know himself, therefore, cannot do better than to examine what are his habits, and which is the predominant one among them. (e) Habits are a prophecy of the future. Habits are not irresistible and do not destroy freedom, but they produce such ease and readiness for acting in one particular way that the probabilities are, when habits are strong, that a person will continue to follow them in the future as he has done in the past, thus progressing or deteriorating, as the case may be. 141. Duties as regards Habits.--(a) Bad habits should be avoided and those that have been formed should be destroyed (see 138). The means to accomplish these victories are divine help obtained through prayer and the other instrumentalities of grace, watchfulness through self-examination, and the cultivation of a spirit of self-denial, as well as attack made on the habit that is forming or already formed (see 255 sqq.) (b) Good habits should be acquired, and those already possessed should be exercised and put to the best advantage. The means to this end, in addition to those that are supernatural, are especially a realization of the importance of good habits, a great desire to have them, and constant and regular effort to practise them (see 137). Art. 2: GOOD HABITS OR VIRTUES (_Summa Theologica_, I-II, qq. 55-70.) 142. Definition.--A virtue is a good habit of the free powers of the soul, that is a principle of good conduct, and never of conduct that is evil. Hence, the following are not virtues: (a) an occasional inclination to good, for this is not a fixed habit; (b) good habits of the body or of the vegetative powers, etc. (such as beauty and health), for these are not free; (c) knowledge of the right or affection for it without any reference to practice, for virtue is a principle of right living; (d) habits that can be applied indifferently to good or bad conduct, such as human opinion. 143. Division.--The virtues are divided: (a) according to their different causes, into infused and acquired virtues (cfr. 134 sqq.);(b) according to their different objects, into intellectual, moral and theological virtues. 144. The intellectual virtues are those habits that perfect the intellect with reference to its good--i.e., truth, speculative or practical. 145. The speculative virtues are three: understanding, knowledge and wisdom.