Commonplace Book
“What I cannot create, I do not understand.”
— Richard Feynman, from his Caltech blackboard, 1988. For a lab that makes matter with light, this is the sentence.
On thinking and questioning
The unexamined life is not worth living.
I cannot teach anybody anything. I can only make them think. (attributed)
To find yourself, think for yourself. (attributed)
— Socrates (c. 470–399 BC), philosopher; the first as recorded in Plato’s Apology
The important thing is not to stop questioning. Curiosity has its own reason for existing.
Look deep into nature, and then you will understand everything better. (attributed)
No problem can be solved from the same level of consciousness that created it. (attributed)
— Albert Einstein (1879–1955), physicist; the first from LIFE, 1955
The scientist is not the person who gives the right answers, but the one who asks the right questions.
— Claude Lévi-Strauss (1908–2009), anthropologist, The Raw and the Cooked, 1964
Science is a way of thinking much more than it is a body of knowledge.
We live in a society absolutely dependent on science and technology and yet have cleverly arranged things so that almost no one understands science and technology. That’s a clear prescription for disaster.
— Carl Sagan (1934–1996), astronomer and author
What is a scientist after all? It is a curious man looking through a keyhole, the keyhole of nature, trying to know what’s going on.
— Jacques-Yves Cousteau (1910–1997), explorer and oceanographer
The scientist is motivated primarily by curiosity and a desire for truth.
— Irving Langmuir (1881–1957), chemist and physicist (attributed)
On making and understanding
Nature uses only the longest threads to weave her patterns, so that each small piece of her fabric reveals the organization of the entire tapestry.
— Richard Feynman (1918–1988), physicist, The Character of Physical Law, 1965
In the fields of observation, chance favors only the prepared mind.
— Louis Pasteur (1822–1895), chemist and microbiologist, Lille, 1854
Self-education is, I firmly believe, the only kind of education there is.
— Isaac Asimov (1920–1992), author and biochemist
Tell me and I forget. Teach me and I may remember. Involve me and I learn.
— after Xunzi (c. 310–235 BC), Confucian philosopher; popularly misattributed to Benjamin Franklin and to Confucius
Education is a social process. Education is growth. Education is not a preparation for life; education is life itself.
— John Dewey (1859–1952), philosopher and educational reformer
On persistence and courage
If you hear a voice within you say “you cannot paint,” then by all means paint, and that voice will be silenced.
— Vincent van Gogh (1853–1890), painter, letter to Theo, 1883
Life is not easy for any of us. But what of that? We must have perseverance and above all confidence in ourselves. We must believe that we are gifted for something and that this thing must be attained.
I have frequently been questioned, especially by women, of how I could reconcile family life with a scientific career. Well, it has not been easy.
Nothing in life is to be feared, it is only to be understood. Now is the time to understand more, so that we may fear less. (attributed)
— Marie Curie (1867–1934), physicist and chemist; Nobel Prizes in Physics and in Chemistry
Above all, don’t fear difficult moments. The best comes from them.
— Rita Levi-Montalcini (1909–2012), neurologist, Nobel Prize in Physiology or Medicine
The greater danger for most of us lies not in setting our aim too high and falling short, but in setting our aim too low and achieving our mark.
— Michelangelo (1475–1564), sculptor, painter, architect, and poet (attributed)
People don’t seem to realize how often you have to come in second in order to finish first. I’ve never met a winner who hadn’t learned to be a loser.
— Jack Nicklaus (1940– ), golfer (attributed)
If you want to succeed, double your failure rate. (attributed)
Follow the path of the unsafe, independent thinker. Expose your ideas to the danger of controversy. Speak your mind and fear less the label of “crackpot” than the stigma of conformity.
— Thomas J. Watson (1874–1956), chairman of IBM
The difference between a successful person and others is not a lack of strength, not a lack of knowledge, but rather a lack of will.
— Vince Lombardi (1913–1970), American football coach (attributed)
The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man.
Success does not consist in never making mistakes but in never making the same one a second time. (attributed)
— George Bernard Shaw (1856–1950), playwright; Nobel Prize in Literature 1925 and Academy Award 1938
Get it right or let it alone. The conclusion you jump to may be your own.
— James Thurber (1894–1961), author and cartoonist, Fables for Our Time
The secret of getting ahead is getting started.
— Mark Twain (1835–1910), author (attributed)
For true success ask yourself these four questions: Why? Why not? Why not me? Why not now?
— James Allen (1864–1912), writer (attributed)
Initiative is doing the right thing without being told.
— Elbert Hubbard (1856–1915), writer and publisher
On people and purpose
Every child is an artist. The problem is how to remain an artist once we grow up.
Action is the foundational key to all success.
— Pablo Picasso (1881–1973), painter and sculptor (both attributed)
One person with passion is better than forty people merely interested.
— E. M. Forster (1879–1970), writer (attributed)
Never doubt that a small group of thoughtful, committed citizens can change the world. Indeed, it is the only thing that ever has.
I measure success in terms of the contributions an individual makes to her fellow human beings.
— Margaret Mead (1901–1978), anthropologist (attributed)
We can’t help everyone, but everyone can help someone.
— Ronald Reagan (1911–2004), 40th U.S. president (attributed)
Be kind whenever possible. It is always possible.
— the 14th Dalai Lama (1935– ), spiritual leader of Tibetan Buddhism
Do not be satisfied with the stories that come before you. Unfold your own myth.
As you start to walk out on the way, the way appears.
— Rumi (1207–1273), poet and jurist, as rendered by Coleman Barks
Home
Peace at home, peace in the world.
My spiritual heritage is science and the mind. Generations after me will confirm that perhaps we could not reach the goals completely because of serious and deep-rooted difficulties, but they will also confirm that we never gave way to compromises and that we have been guided by the mind and science.
— Mustafa Kemal Atatürk (1881–1938), founder of the Republic of Turkey
“(attributed)” marks lines that are popular but not traceable to the person’s own words. Updated September 2026.