Always recognize that human individuals are ends, and do not use them as means to your end.

So act that anything you do may become universal law.

Even a man's exact imitation of the song of the nightingale displeases us when we discover that it is a mimicry, and not the nightingale.

Give a man everything he wants and at that moment everything is not everything

Two things fill the mind with ever-increasing wonder and awe, the more often and the more intensely the mind of thought is drawn to them: the starry heavens above me and the moral law within me... Morality is not properly the doctrine of how we may make ourselves happy, but how we may make ourselves worthy of happiness.

Innocence is indeed a glorious thing; but, unfortunately, it does not keep very well and is easily led astray.

Animals... are there merely as a means to an end. That end is man.