Aquinas sees reason and faith as two ways of knowing. “Reason” covers what we can know by experience and logic alone. From reason, we can know that there is a God and that there is only one God; these truths about God are accessible to anyone by experience and logic alone, apart from any special revelation from God.

liberation theology, religious movement arising in late 20th-century Roman Catholicism and centred in Latin America. It sought to apply religious faith by aiding the poor and oppressed through involvement in political and civic affairs.

Thomas Aquinas was the greatest of the Scholastic philosophers. He produced a comprehensive synthesis of Christian theology and Aristotelian philosophy that influenced Roman Catholic doctrine for centuries and was adopted as the official philosophy of the church in 1917.

Gustavo Gutierrez, a Peruvian Roman Catholic priest and theologian, defines liberation theology as a “theological reflection based on the Gospel and the experiences of men and women committed to the process of liberation in this oppressed and exploited sub-continent of Latin America.

The theory of liberation theology had a direct impact on Central America in the 1970s since it justified the alliance of Christians and Marxists in attempting to overthrow repressive regimes in Nicaragua and El Salvador.

They are:

• the argument from “first mover”;
• the argument from causation;
• the argument from contingency;
• the argument from degree;
• the argument from final cause or ends (“teleological argument”).

Aquinas posits a “twofold mode of truth concerning what we profess about God” ( SCG 1.3.2). First, we may come to know things about God through rational demonstration. By demonstration Aquinas means a form of reasoning that yields conclusions that are necessary and certain for those who know the truth of the demonstration’s premises.

Although Aquinas does not think that philosophical reasoning can provide an exhaustive account of the divine nature, it is (he insists) both a source of divine truth and an aid in exonerating the intellectual credibility of those doctrines at the heart of the Christian faith.

Aquinas is not claiming that our demonstrative efforts will give us complete knowledge of God’s nature. He does think, however, that human reasoning can illuminate some of what the Christian faith professes ( SCG 1.2.4; 1.7).

Aquinas’ argument in the first way—which is structurally similar to the argument from efficient causality—employs a parallel line of reasoning. There, he says that to be in motion is to move from potentiality to actuality. When something moves, it goes from having the ability to move to the activity of moving.