Kant believed that there is an 'objective moral law ' this meant, he did not depend on a point of view. If there is a moral law there is a duty to obey this law. To act morally, it is necessary to have a good will for example to help someone just because it would be the right thing to do in the certain situation. Morality is made up of 'categorical imperatives ' meaning that you should do something simply because they are the correct things to do, as you are expected to fulfill things in life this is called a certain 'duty '.
Kant believed that there were specific categories on how to understand the world, we would understand them by: time, space and causality, however the mind has categories for many experiences, nobody can prove in the world that anything has a cause, we can assume that it does and only confirm it by certain experiences that we face. Kant argued that we cannot prove to do something just by analysing it, as we will never have enough evidence, if there is a moral law we would have a duty to obey that law as it is the right thing to do. Kant belived that being rational is the answer to morality, because of this belief it would be right to say that all rational beings would need to have the exact same moral laws, and that the moral laws would have an absolute requirement which would be applied universally to all rational beings. If an action is to be moral, other than it being a universal law, also could only come from a duty by itself. A 'duty ' is when respecting the law you do something, for example to help an old lady cross the road, morally this would be someone 's duty to help her as according to Kant this would be the right thing to do. Kant can tell the different through two duties: this would be a perfect and imperfect duty. A perfect duty is would be where someone would not be treated as a mean to an end, whereas imperfect duties would require treating people as