Doubt is a pain too lonely to know that faith is his twin brother. (Quote by - Kahlil Gibran)

To be once in doubt Is once to be resolved. (Quote by - William Shakespeare)

We know accurately only when we know little; with knowledge doubt increases. (Quote by - Goethe)

Uncertain ways unsafest are, And doubt a greater mischief than despair. (Quote by - Sir John Denham)

The only limit to our realization of tomorrow will be our doubts of today. (Quote by - Franklin Delano Roosevelt)

Our doubts are traitors, And make us lose the good we oft might win, By fearing to attempt. (Quote by - William Shakespeare)

Philosophy when superficially studied, excites doubt, when thoroughly explored, it dispels it. (Quote by - Francis Bacon)

Doubt is the father of invention. (Quote by - Galileo)

Who never doubted, never half believed. Where doubt there truth is--'tis her shadow. (Quote by - Philip James Bailey)

Doubting charms me not less than knowledge. (Quote by - Dante)

Doubt indulged soon becomes doubt realized. (Quote by - Frances R. Havergal)

Believe while others are doubting. (Quote by - William Arthur Ward)

There lives more faith in honest doubt, Believe me, than in half the creeds (Quote by - Lord Alfred Tennyson)

Doubt is the vestibule through which all must pass before they can enter into the temple of wisdom. (Quote by - Colton)

Ten thousand difficulties do not make one doubt. (Quote by - John Henry Newman)

The doubtful beam long nods from side to side. (Quote by - Alexander Pope)

I respect faith, but doubt is what gets you an education. (Quote by - Wilson Mizner)