beginning of things and their last end, and especially of rational creature…” (Aquinas 22). The sacred doctrine, or theology, is directed to teach about God’s beliefs and also how he created things, such as ourselves. He divides the topic of God’s existence into 3 articles: “Whether the existence of God is self-evident?”, “whether it can be demonstrated that God exists?”, and “whether God exists?” To the first article, Aquinas responds “ A thing can be self-evident in either of two ways: on the one hand, self-evident in itself, though not to us; on the other, self-evident in itself, and to us” (Aquinas 23). Things can have essence with or without existence. We do not know God’s essence, so he is not self-evident to us, but it can be established by the things that are already self-evident to us. In response to the second article, Aquinas explains that we can establish this by two ways. “One is through cause,and is called ‘a priori,’ and this is to argue from what is prior absolutely. The other is through the effect, and is called a demonstration ‘a posteriori’; this is to argue from what is prior relatively only to us” (Aquinas 25). A priori refers to our knowledge before any experience and a posteriori refers to our knowledge after our experiences. He goes on to explain that if we are more familiar with the effects of something, then we can attempt to find and know the cause as well. An object must always have something that previously existed before it, in order for the object to have been created or derived from the previous one. The effect always follows the cause which is pre-existing. Objects and beings on Earth always have first principles, but how did these first principles come about? Does there need to be a force that initiates change within these things? According to Aquinas, the effects must be proportionate to the causes in order for us to gain knowledge of that specific cause. He states, “Yet from every effect the existence of the cause can be clearly demonstrated, and so we can demonstrate the existence of God from His effects; though from them we cannot perfectly know God as He is in His essence” (Aquinas 26). If God created all things and beings on this Earth, those are the effects and he is the cause of those effects. Since we know the effects, we can demonstrate God’s existence and believe in God’s existence, however we cannot know God. In the third article, the two objections suppose that God does not exist because God is good and if he did exist, there would be no evil in the world but there is evil in the world. Also, not everything in the world must be traced back to being created by God, they could have just been created due to one basic principle, nature. Aquinas responds to these objections with five different arguments. He argues that things in the world are in motion, but something or someone must be able to start the wave of motion. So, he says it is not possible for something to move itself. If something is in motion, it continues to put the next thing in motion and so on. This is similar to Newton’s first law of motion, “Every object in a state of uniform motion will remain in that state of motion unless an external force acts on it.” However, there has to be a “first mover” because this cycle cannot go on for infinity with having had a start. Becasue of this reasoning, the only thing or person who would be this “first mover,” we accept to be God. In his next argument, he states, “ In the world of sense we find there is an order of efficient causes” (Aquinas 27). No object or being is a cause of itself, this is impossible because then it would be previous to itself. If there was no cause, there is no effect. With no first cause, there would not be a final effect, therefore we understand the first cause as God. The third argument Aquinas