Two things fill the mind with ever new and increasing admiration and awe, the oftener and more steadily we reflect on them: the starry heavens above and the moral law within.

Freedom can never be comprehended, nor even can insight into it be gained.

The only thing that is good without qualification is a good will.

The question is not so much whether there is life on Mars as whether it will continue to be possible to live on Earth

But although all our knowledge begins with experience, it does not follow that it arises from experience.

An action is essentially good if the motive of the agent be good, regardless of the consequences.

Act in such a way that you treat humanity, whether in your own person or in the person of any other, never merely as a means to an end, but always at the same time as an end.