In a general sense, moral virtues are any positive personal qualities that lead a person to lead a life characterized by self-control, altruism and good acts. In a more specific sense, the moral virtues are a part of the Catholic catechism that advise a believer about the ways to lead a good and pure life.
Justice, as applied to morality on an individual level, is the willingness to recognize the impact of both good and bad actions. A person who is committed to justice will reward the good in both himself and others, and will punish the bad. A just person who has done something wrong won't complain about the consequences, but will recognize that justice must be done and will accept the consequences of his actions with equanimity. The concept of justice in Western philosophy and religion is roughly comparable to the idea of karma in the East.
Temperance is the quality of self-control and moderation. It may be applied to the intake of alcohol and food, sexual passion or any urge or desire that has the power to overcome the balance of a person's mind. A person who has developed temperance in herself is able to step away from momentary urges and to look at them objectively, thus reducing their power to control her mind. The word "temperance" was widely used in the early 20th century in connection with campaigns against alcohol. Any attempt at self-control and moderation is an exercise in temperance.
Prudence is related to temperance but encompasses a wider variety of thoughts, activities and circumstances. A prudent person doesn't act rashly, but considers the impact and results of his actions. Prudence implies presence of mind, reason and the ability to predict future outcomes, whether positive or negative. Prudent people are reserved in spending, dedicated to the safety of those who are dependent on them and committed to avoiding extremes in thought or action. Prudence implies prioritizing the needs of a community over one's personal desires.
Fortitude is another word for strength and determination. A person who pursues the virtues of justice, temperance, and prudence will also require fortitude in a world that is not only not dedicated to these things, but actively seduces people away from them in favor of indulgence and short-term pleasure. Fortitude included self-confidence in the rightness of one's own actions, immunity to the condemnations or mockery of other people, and faith in the personal philosophy that underlies unpopular decisions. A mindset that is grounded in fortitude can actually be strengthened rather than weakened by opposition.