It may be doubtful, at first, whether a person is an enemy or friend. Meat, if not properly digested, becomes poison; But poison, if used rightly, may turn medicinal.
Saskya Pandita( 1182-1251) Tibetan Grand Lama

To have doubted one's own first principles is the mark of a civilized man.
Sr Oliver Wendell Holmes( 1809-1894) American Author, Wit and Poet

Melt and dispel, ye spectre-doubts, that roll Cimmerian darkness o'er the parting soul!
Thomas Campbell 1777-1844.

Skepticism means not intellectual doubt alone, but moral doubt.
Thomas Carlyle( 1795-1881) Scottish Author and Philosopher

The fearful unbelief is unbelief in yourself.
Thomas Carlyle( 1795-1881) Scottish Author and Philosopher

Doubt, of whatever kind, can be ended by action alone.
Thomas Carlyle( 1795-1881) Scottish Author and Philosopher

The natural cause of the human mind is certainly from credulity to skepticism.
Thomas Jefferson( 1743-1826) American...3rd President of the U.S

Thus, when the lamp that lighted The traveller at first goes out, He feels awhile benighted, And looks around in fear and doubt. But soon, the prospect clearing, By cloudless starlight on he treads, And thinks no lamp so cheering As that light which Heaven sheds.
Thomas Moore.( 1779-1852) Irish Poet

Despair is a mental state which exaggerates not only our misery but also our weakness.
Vauvenargues(1715-1747) French Moralist

Confidence is nowhere safe.
Vergil ( B.C. 70-19) Roman Epic, Didactic, and Idyllic Poet

An honest man can never surrender an honest doubt.
Walter Malone( 1866-1915) American Jurist

If the Sun and Moon should doubt. They'd immediately Go out.
William Blake( 1757-1828) English Poet and Artist

Our belief at the beginning of a doubtful undertaking is the one thing that assures the successful outcome of any venture.
William James( 1842-1910) American Philosopher and Author

Modest doubt is called the beacon of the wise.
William Shakespeare( 1564-1616) English Dramatist and Poet

Our doubts are traitors, and make us lose the good we oft might win by fearing to attempt.
William Shakespeare( 1564-1616) English Dramatist and Poet

But now I am cabin'd, cribb'd, confined, bound in To saucy doubts and fears.
William Shakespeare( 1564-1616) English Dramatist and Poet

Where love is great, the littlest doubts are fear; When little fears grow great, great love grows there.
William Shakespeare( 1564-1616) English Dramatist and Poet

Doubt thou the stars are fire; Doubt that the sun doth move; Doubt truth to be a liar; But never doubt I love.
William Shakespeare( 1564-1616) English Dramatist and Poet

I respect faith, but doubt is what gets you an education.
Wilson Mizner No Bio Data

When you doubt, abstain.
Zoroaster( B.C. 628?-551?) Persian Religious Leader-Founder of Zoroastrianism

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