Epictetus, Golden Sayings 33

Do you know what a speck you are in comparison with the Universe?

That is, with respect to the body; since with respect to Reason, you are not inferior to the Gods, nor less than they. 

For the greatness of Reason is not measured by length or height, but by the resolves of the mind. 

Place then your happiness in that wherein you are equal to the Gods.