made from them, but also on account of the excellence and purity of their substance." Thomas Aquinas also wrote extensively on usury, that is, the lending of money with interest. He condemned its practice: "to take usury for money lent is unjust in itself, because this is to sell what does not exist, and this evidently leads to inequality which is contrary to justice." Money, and other similar goods, are consumed only when they are used. Charging a premium for money lent is a charge for more than the use of the good. Thus, Thomas Aquinas concluded that the lender is charging for something not his own, in other words, not rendering to each his due. Usury The Second Lateran Council called the practice of loaning money "detestable and shameful... insatiable rapacity of money lenders, forbidden both by divine and human laws throughout the Old and New Testament, we condemn, and separate from the ecclesiastical consolation". The Fifth Lateran Council defined usury as "when, from its use, a thing which produces nothing is applied to the acquiring of gain and profit without any work, any expense or any risk". Modern Western views concerning capitalism, unfair labor practice, living wage, price gouging, monopolies, fair trade practices, and predatory pricing, inter alia, are remnants of the inculcation of Aquinas' interpretation of natural moral law. Theology Thomas Aquinas viewed theology, or the sacred doctrine, as a science, the raw material data of which consists of written scripture and the tradition of the Catholic Church. These sources of data were produced by the self-revelation of God to individuals and groups of people throughout history. Faith and reason, while distinct but related, are the two primary tools for processing the data of theology. Thomas believed both were necessary—or, rather, that the confluence of both was necessary—for one to obtain true knowledge of God. Thomas blended Greek philosophy and Christian doctrine by suggesting that rational thinking and the study of nature, like revelation, were valid ways to understand truths pertaining to God. According to Thomas, God reveals himself through nature, so to study nature is to study God. The ultimate goals of theology, in Thomas's mind, are to use reason to grasp the truth about God and to experience salvation through that truth. The central thought is "gratia non tollit naturam, sed perficit" ('grace does not destroy nature, but perfects it'). Revelation Thomas believed that truth