This document outlines the cosmological argument and various philosophical perspectives on it. The cosmological argument proposes that the universe must have an explanation for its existence, and that God provides the best explanation as something that requires no further explanation. Thinkers like Aquinas, Leibniz, and Copleston proposed versions of the argument. More recently, the Kalam cosmological argument posits that the universe could not be past eternal and therefore requires a cause. The document also discusses strengths like its logical coherence, and weaknesses such as whether the first premise that the universe requires an explanation can be assumed. It concludes by mentioning skeptical philosophies of Hume and Kant regarding causality and the limits of human knowledge.