Knowing yourself is the beginning of all wisdom.
Happiness depends upon ourselves.
The whole is greater than the sum of its parts.
The opinions which Milton, Locke, and others have so ably sustained, I firmly believe to be correct.
Don't explain your philosophy. Embody it.
Death does not concern us, because as long as we exist, death is not here. And when it does come, we no longer exist.
God is dead. God remains dead. And we have killed him.
And if you gaze long enough into an abyss, the abyss will gaze back into you.
There are no facts, only interpretations.
The opposite of a correct statement is a false statement. But the opposite of a profound truth may well be another profound truth.
What one man calls God, another calls the laws of physics.
To define is to limit.
I think, therefore I am.
Doubt is the origin of wisdom.
The unexamined life is not worth living.
Wonder is the beginning of wisdom.
Anxiety is the dizziness of freedom.
It is perfectly true, as the philosophers say, that life must be understood backwards. But they forget the other proposition, that it must be lived forwards.
Chemistry is the study of matter, but I prefer to see it as the study of change.
There is nothing either good or bad, but thinking makes it so.
Two things fill the mind with ever new and increasing admiration and awe: the starry heavens above me and the moral law within me.
Out of the crooked timber of humanity, no straight thing was ever made.
Thoughts without content are empty, intuitions without concepts are blind.
All our knowledge begins with the senses, proceeds then to the understanding, and ends with reason.
Plato is my friend, Aristotle is my friend, but my greatest friend is truth.
The philosophers have only interpreted the world, in various ways. The point, however, is to change it.
Necessity is blind until it becomes conscious. Freedom is the consciousness of necessity.
Reason has always existed, but not always in a reasonable form.
The Tao that can be told is not the eternal Tao. The name that can be named is not the eternal name.
In rivers, the water that you touch is the last of what has passed and the first of that which comes; so with present time.
Music is a higher revelation than all wisdom and philosophy.
We will not learn theory well unless we have been practicing it.
In order to protect ourselves we must live like doctors and be continually treating ourselves with reason.
Could there be a more profitable study than this - the study of how to live?
Have I played the part well? Then applaud as I exit.
Nothing can be created from nothing.
Death is nothing to us, since when we are, death has not come, and when death has come, we are not.
Human action is purposeful behavior.
He is the wisest philosopher who holds his theory with some doubt.
Happiness is not the reward of virtue, but is virtue itself.
Desire is the very essence of man.
In the mind there is no absolute or free will; but the mind is determined to wish this or that by a cause, which has also been determined by another cause, and so on to infinity.
Hell hath no limits, nor is circumscribed in one self place; for where we are is hell, and where hell is, there must we ever be.
Why is there anything at all rather than nothing whatsoever?
The present is saturated with the past and pregnant with the future.
There is nothing without a reason.
The optimist thinks this is the best of all possible worlds. The pessimist fears it is true.
Hell is other people.
Existence precedes essence.
Everything has been figured out, except how to live.
