The secret of getting things done is to act.
I love to doubt as well as know.
Nature does nothing in vain.
The energy of the mind is the essence of life.
I worked hard. Anyone who works as hard as I did can achieve the same results.
A jug fills drop by drop.
Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense.
Do not dwell in the past, do not dream of the future, concentrate the mind on the present moment.
He is able who thinks he is able.
It is better to travel well than to arrive.
No one saves us but ourselves. No one can and no one may. We ourselves must walk the path.
The mind is everything. What you think you become.
The only real failure in life is not to be true to the best one knows.
There are only two mistakes one can make along the road to truth; not going all the way, and not starting.
To be idle is a short road to death and to be diligent is a way of life; foolish people are idle, wise people are diligent.
Three things cannot be long hidden: the sun, the moon, and the truth.
Your work is to discover your world and then with all your heart give yourself to it.
Attitude is a little thing that makes a big difference.
Difficulties mastered are opportunities won.
However beautiful the strategy, you should occasionally look at the results.
If you are going through hell, keep going.
Never, never, never give up.
It does not matter how slowly you go so long as you do not stop.
Our greatest glory is not in never falling, but in getting up every time we do.
Study the past if you would define the future.
Wheresoever you go, go with all your heart.
By nature, men are nearly alike; by practice, they get to be wide apart.
Hold faithfulness and sincerity as first principles.
Learning without thought is labor lost; thought without learning is perilous.
The cautious seldom err.
The determined scholar and the man of virtue will not seek to live at the expense of injuring their virtue. They will even sacrifice their lives to preserve their virtue complete.
The man of virtue makes the difficulty to be overcome his first business, and success only a subsequent consideration.
The scholar who cherishes the love of comfort is not fit to be deemed a scholar.
When you know a thing, to hold that you know it; and when you do not know a thing, to allow that you do not know it - this is knowledge.
A scientific man ought to have no wishes, no affections, - a mere heart of stone.
To kill an error is as good a service as, and sometimes even better than, the establishing of a new truth or fact.
...it is always advisable to perceive clearly our ignorance.
The very essence of instinct is that it's followed independently of reason.
Imagination is more important than knowledge.
The only real valuable thing is intuition.
Anyone who has never made a mistake has never tried anything new.
Everything should be made as simple as possible, but not simpler.
The important thing is not to stop questioning. Curiosity has its own reason for existing.
Two things are infinite: the universe and human stupidity; and I'm not sure about the universe.
The whole of science is nothing more than a refinement of everyday thinking.
Further, the dignity of the science itself seems to require that every possible means be explored for the solution of a problem so elegant and so celebrated.
I have had my results for a long time: but I do not yet know how I am to arrive at them.
It is not knowledge, but the act of learning, not possession but the act of getting there, which grants the greatest enjoyment.
The enchanting charms of this sublime science reveal only to those who have the courage to go deeply into it.
He who seeks for methods without having a definite problem in mind seeks in the most part in vain.
All our knowledge begins with the senses, proceeds then to the understanding, and ends with reason. There is nothing higher than reason.
Experience without theory is blind, but theory without experience is mere intellectual play.
Thoughts without content are empty, intuitions without concepts are blind.
I much prefer the sharpest criticism of a single intelligent man to the thoughtless approval of the masses.
Nature uses as little as possible of anything.
Truth is the daughter of time, and I feel no shame in being her midwife.
What we know is not much. What we do not know is immense.
All that is not perfect down to the smallest detail is doomed to perish.
Discipline, work. Work, discipline.
I am hitting my head against the walls, but the walls are giving way.
It's not just a question of conquering a summit previously unknown, but of tracing, step by step, a new pathway to it.
If I have done the public any service, it is due to my patient thought.
If I have seen further than others, it is by standing upon the shoulders of giants.
Imagination decides everything.
Men blaspheme what they do not know.
Small minds are concerned with the extraordinary, great minds with the ordinary.
Practise what you know, and it will help to make clear what now you do not know.
Old age is a hindrance to creativity but cannot crush my youthful spirit.
Everything is vague to a degree you do not realize till you have tried to make it precise.
I would never die for my beliefs because I might be wrong.
The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
A stupid man's report of what a clever man says can never be accurate, because he unconsciously translates what he hears into something he can understand.
Ideas are like rabbits. You get a couple and learn how to handle them, and pretty soon you have a dozen.
It is a common experience that a problem difficult at night is resolved in the morning after the committee of sleep has worked on it.