The excessive increase of anything causes a reaction in the opposite direction.

Plato  (427–347 BC)

Better a little which is well done, than a great deal imperfectly.

Plato  (427–347 BC)

All things will be produced in superior quantity and quality, and with greater ease, when each man works at a single occupation, in accordance with his natural gifts, and at the right moment, without meddling with anything else.

Plato  (427–347 BC)

No one ever teaches well who wants to teach, or governs well who wants to govern.

Plato  (427–347 BC)

Opinion is the medium between knowledge and ignorance.

Plato  (427–347 BC)

We can easily forgive a child who is afraid of the dark; the real tragedy of life is when men are afraid of the light.

Plato  (427–347 BC)

Nothing is enough for the man to whom enough is too little.

Epicurus  (341–270 BC)

Not what we have but what we enjoy, constitutes our abundance.

Epicurus  (341–270 BC)

Do not spoil what you have by desiring what you have not; remember that what you now have was once among the things you only hoped for.

Epicurus  (341–270 BC)

Think like a man of action, and act like a man of thought.

Sallust  (86–34 BC)

All those who offer an opinion on any doubtful point should first clear their minds of every sentiment of dislike, friendship, anger or pity.

Sallust  (86–34 BC)

Whenever the speech is corrupted so is the mind.

Lucius Annaeus Seneca  (4 BC – AD 65)

Luck is what happens when preparation meets opportunity.

Lucius Annaeus Seneca  (4 BC – AD 65)

Expecting is the greatest impediment to living.  In anticipation of tomorrow, it loses today.

Lucius Annaeus Seneca  (4 BC – AD 65)

Time heals what reason cannot.

Lucius Annaeus Seneca  (4 BC – AD 65)

Know how to listen, and you will profit even from those who talk badly.

Plutarch  (AD 46–120)

We have two ears and one mouth so that we can listen twice as much as we speak.

Epictetus  (AD 55 – AD 135)

Wealth consists not in having great possessions, but in having few wants.

Epictetus  (AD 55 – AD 135)

The desire for safety stands against every great and noble enterprise.

Tacitus  (AD 56–115)

Simplicity is the ultimate sophistication.

Leonardo da Vinci  (1452–1519)

Beware the fury of a patient man.

John Dryden,  (1631–1700)

We are to admit no more causes of natural things than such as are both true and sufficient to explain their appearances.

Isaac Newton  (1643–1727)

By failing to prepare, you are preparing to fail.

Benjamin Franklin  (1706–1790)

The definition of insanity is doing the same thing over and over and expecting different results.

Benjamin Franklin  (1706–1790)

Beware of little expenses.  A small leak will sink a great ship.

Benjamin Franklin  (1706–1790)

Hear reason, or she'll make you feel her.

Benjamin Franklin  (1706–1790)

Life's tragedy is that we get old to soon and wise too late.

Benjamin Franklin  (1706–1790)

Worry is the interest paid by those who borrow trouble.

George Washington  (1732–1799)

My observation is that whenever one person is found adequate to the discharge of a duty...  it is worse executed by two persons, and scarcely done at all if three or more are employed therein.

George Washington  (1732–1799)

Determine never to be idle.  No person will have occasion to complain of the want of time who never loses any.  It is wonderful how much may be done if we are always doing.

Thomas Jefferson  (1743–1826)

I may lose a battle but I will never lose a minute.

Napoleon  (1769–1821)

Do not go where the path may lead, go instead where there is no path and leave a trail.

Ralph Waldo Emerson  (1803–1882)

Be sure you put your feet in the right place, then stand firm.

Abraham Lincoln  (1809–1865)

Give me six hours to chop down a tree, and I will spend the first four sharpening the axe.

Abraham Lincoln  (1809–1865)

The young man knows the rules, but the old man knows the exceptions.

Oliver Wendell Holmes, Sr.  (1809–1894)

Irrationally held truths may be more harmful than reasoned errors.

Thomas Henry Huxley  (1825–1895)

Everyone thinks of changing the world, but no one thinks of changing himself.

Leo Tolstoy  (1828–1910)

When I was a boy of 14, my father was so ignorant I could hardly stand to have the old man around.  But when I got to be 21, I was astonished at how much the old man had learned in seven years.

Mark Twain  (1835–1910)

We make a living by what we get, but we make a life by what we give.

Winston Churchill  (1874–1965)

Solitary trees, if they grow at all, grow strong.

Winston Churchill  (1874–1965)

If you are going through hell, keep going.

Winston Churchill  (1874–1965)

No folly is more costly than the folly of intolerant idealism.

Winston Churchill  (1874–1965)

If the past sits in judgment on the present, the future will be lost.

Winston Churchill  (1874–1965)

Be nice to people on your way up because you meet them on the way down.

Wilson Mizner  (1876–1933)

Not everything that can be counted counts, and not everything that counts can be counted.

Albert Einstein  (1879–1955)

Make everything as simple as possible, but not simpler.

Albert Einstein  (1879–1955)

Perfection of means and confusion of ends seem to characterize our age.

Albert Einstein  (1879–1955)

It's not that I'm so smart, it's just that I stay with problems longer.

Albert Einstein  (1879–1955)

Time sanctifies everything; even the most arrant theft in the hands of the robber's grandchildren becomes sacred and inviolable property.

Will Durant  (1885–1981)
"The Story of Civilization" 1 (11), Our Oriental Heritage, 1935

Wherever men do things, other men will arise who will explain to them how things should be done.

Will Durant  (1885–1981)
"The Story of Civilization" 1 (11), Our Oriental Heritage, 1935

It is one of the most culpable oversights of nature that virtue and beauty so often come in separate packages.

Will Durant  (1885–1981)
"The Story of Civilization" 1 (11), Our Oriental Heritage, 1935

Education is learning what you didn't even know you didn't know.

Daniel Boorstin  (1914–2004)

Knowledge is not simply another commodity.  On the contrary.  Knowledge is never used up.  It increases by diffusion and grows by dispersion.

Daniel Boorstin  (1914–2004)

We read advertisements...  to discover and enlarge our desires.  We are always ready — even eager — to discover, from the announcement of a new product, what we have all along wanted without really knowing it.

Daniel Boorstin  (1914–2004)

We suffer primarily not from our vices or our weaknesses, but from our illusions.  We are haunted, not by reality, but by those images we have put in their place.

Daniel Boorstin  (1914–2004)

If a principle exists it must be immutable, for that is what a principle is — a truth standing apart from the mood of the times.

Jeff Cooper  (1920–2006)
"Principles of Personal Defense", 1989

When you are doing one thing — talking on your phone, texting, whatever — you are automatically not doing something else.  What is the greatest scarcity in the world today?  It's not oil.  It's time.  Time is precious.  Don't throw it away.

Martin Cooper  (inventor)  (Born 1928)
"Did cell phones unleash our inner rudeness?", 2011

In theory, there is no difference between theory and practice.
But, in practice, there is.

Jan L.A. van de Snepscheut  (1953–1994)