“Nobody grows old merely by living a number of years. We grow old by deserting our ideals. Years may wrinkle the skin, but to give up enthusiasm wrinkles the soul”

“Unquestionably, it is possible to do without happiness; it is done involuntarily by nineteen-twentieths of mankind”

“The two enemies of human happiness are pain and boredom ”

“Always leave something to wish for; otherwise you will be miserable from your very happiness”

“None are so old as those who have outlived enthusiasm ”

“If you cannot work with love but only with distaste, it is better that you should leave your work. ”