THERE ARE TWO THINGS that don't have to mean anything, one is music and the other is laughter.

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

Every human being should always be treated as an end and never as a mere instrument.

If a man is often the subject of conversation he soon becomes the subject of criticism.

All our knowledge begins with the senses...

Always regard every man as an end in himself, and never use him merely as a means to your ends [i.e., respect that each person has a life and purpose that is their own; do not treat people as objects to be exploited].

Intuition and concepts constitute... the elements of all our knowledge, so that neither concepts without an intuition in some way corresponding to them, nor intuition without concepts, can yield knowledge.