At first place in the chapter 1 of GMM, Kant tries to demonstrate that there is a moral law which is driven from the sense of moral obligations. He identifies how the moral law possibly driven from the sense of moral obligations that motive us to act morally. Kant simply implies that a universal moral law that can be only exist in kind of formula determining if an action is moral or not. He named the formula Categorical Imperative which can be basically defined as "Always act so that you can will the rule of your action to be a universal law." It is 'categorical' because it is not 'hypothetical' or 'contingent' on anything, but is always and everywhere 'universal'. Because it is called an 'imperative' and it is a command, not an option, for every action there is a universal rule based on morality of the action. In accordance with this in following parts of chapter 3 of GMM, Kant argues that the existence of morality implies the existence of free will. Roughly, it can be said that if you don't have free will, you can't be moral, because you can't be responsible for your actions. The notion of free will attributes to persons the capacity to choose autonomously among possible alternative actions. This presumed autonomy of the will does not imply that a person's volition is totally immune to influence by other persons or by the natural world. What it does imply is that such heteronymous influences on a person's will not withstanding, there remains a substantial residue of independence of them, by virtue of which her rational faculty remains the final arbiter of what she actually wills. The outcome of this autonomous arbitration process is not capricious or random, but determined by the person's soul (Stent 2). The problem Kant struggles with in the Chapter 3 of GMM is how to make room for the ideas of human choice, reason, and deliberation in a world that we believe to be a world where every event is caused.
