The intellect is the only fit guide for human life.
The light of the body is the eye: therefore when thine eye is single, thy whole body is full of light; but when thine eye is evil, thy body also is full of darkness. Take heed therefore that the light which is in thee be not darkness.
A man who lives an intellectual life is like a man who carries a lantern in front of him to light his way. Such a person will never come to a dark place, because the light of his intellect moves before him. There is no fear of death in this kind of life, because the lantern which moves before you lights your way to your last minute, and you follow it to the end as calmly and quietly as you have all of your life.
Some people live and act according to their own thoughts, and some according to the thoughts of others; this is a crucial distinction between people.