For my part I know nothing with any certainty, but the sight of the stars makes me dream.
Probability is expectation founded upon partial knowledge. A perfect acquaintance with all the circumstances affecting the occurrence of an event would change expectation into certainty, and leave nether room nor demand for a theory of probabilities.
Persuasion is achieved by the speaker's personal character when the speech is so spoken as to make us think him credible. We believe good men more fully and more readily than others: this is true generally whatever the question is, and absolutely true where exact certainty is impossible and opinions are divided.
Whether gods exist or not, there is no way to get absolute certainty about ethics. Without absolute certainty, what do we do? We do the best we can.
Once upon a time, growing up male gave little boys a sense of certainty about the natural order of things. We had short hair, wore pants, and played baseball. Girls had long hair, wore skirts, and, no matter how hard they tried, always threw a baseball just like a girl.
To teach how to live without certainty and yet without being paralysed by hesitation is perhaps the chief thing that philosophy, in our age, can do for those who study it.
People who ask confidently get more than those who are hesitant and uncertain. When you've figured out what you want to ask for, do it with certainty, boldness and confidence. Don't be shy or feel intimidated by the experience. You may face some unexpected criticism, but be prepared for it with confidence.
Benjamin Franklin said there were only two things certain in life: death and taxes. But I'd like to add a third certainty: trash. And while some in this room might want to discuss reducing taxes, I want to talk about reducing trash.
There is no certainty; there is only adventure.
I feel, sometimes, as the renaissance man must have felt in finding new riches at every point and in the certainty that unexplored areas of knowledge and experience await at every turn.