Born in Konigsberg, the starting point for Kant's life work in philosophy was the works of [[David Hume]] who awakened Kant from his "dogmatic slumber" and led him to make his "Copernican revolution in philosophy"<ref>The New American Desk Encyclopedia, Penguin Group, 1989</ref>
In his ''A Critique of Pure Reason'' Kant examined pure [[reason]] as a basis of knowledge. The problem Hume had left Kant was a sharp divide between the ''a priori'' (things that can be known without experience) and the ''a posteori'' (things that could only be known with experience) together with a devastating critique of induction. Hume insisted that ''a priori'' knowledge was entirely ''analytic'' (did not speak of the world) and that the sense data of our experiance experience could never support a proposition that went beyond that experience. Such a position leads to a radical and absolute sketpicism skepticism about even the possibility of knowledge. "A Critique of Pure Reason" seeks to counteract that skepticism by establishing the existence of ''synthetic a priori'' truths, truths that speak of the world but that are known logically prior to looking at the world. To establish those truths Kant looked at the way reason picture the world. No reasoning being can have an experience other than one that involves ''time'' and ''space''. In common language in order to see something it has to be somewhere (iei.e. in space) and it has to be there at sometime (ie i.e. in time). Time and space are necessary conditions of all experience and, thus, we can know of their existence logically prior to any particular experience.
Having established time and space as neccessary necessary preconditions of experience Kant proceeded to question how reason must operate on the experiences presetned presented to it. In this part of the work Kant establishes several "categories" through which reason operates, categories that effect the conclusions that reason must come to.
Kant also suggested a material origin for the solar system (prior to Kant, the origin of the solar system was considered to be immaterial and possibly even a priori). Kant's own suggestion for a moral daily life was the [[categorical imperative]]: ''Act only according to that maxim whereby you can at the same time will that it should become a universal law''. It does not mean that an act is moral only if it works as a rule for everyone as that is consequentialist. Kant uses the example of suicide out of self-love being wrong in that it is contradictory to love oneself and want to commit suicide. Thus, the maxim is contradictory and cannot be a universal law. On the other hand, if a murderer asks you where someone is hiding, you should always tell them because lying is wrong. The categorical imperative can be contrasted with the [[hypothetical imperative]], which says that you should act according to any maxim which might possibly be willed. He remained single throughout his life, though he said, toward the end of it, that he could not afford a wife in his youth and did not need one in his old age. Kant's aim was to make philosophy truly scientific.