Doubt, a status between belief
Belief is the psychological state in which an individual holds a proposition or premise to be true.-Belief, knowledge and epistemology:The terms belief and knowledge are used differently in philosophy....

 and disbelief, involves uncertainty
Uncertainty is a term used in subtly different ways in a number of fields, including physics, philosophy, statistics, economics, finance, insurance, psychology, sociology, engineering, and information science...

 or distrust
Distrust is a formal way of not trusting any one party too much in a situation of grave risk or deep doubt. It is commonly expressed in civics as a division or balance of powers, or in politics as means of validating treaty terms. Systems based on distrust simply divide the responsibility so that...

 or lack of sureness of an alleged fact
A fact is something that has really occurred or is actually the case. The usual test for a statement of fact is verifiability, that is whether it can be shown to correspond to experience. Standard reference works are often used to check facts...

, an action, a motive, or a decision
Decision making
Decision making can be regarded as the mental processes resulting in the selection of a course of action among several alternative scenarios. Every decision making process produces a final choice. The output can be an action or an opinion of choice.- Overview :Human performance in decision terms...

. Doubt brings into question some notion of a perceived "reality
In philosophy, reality is the state of things as they actually exist, rather than as they may appear or might be imagined. In a wider definition, reality includes everything that is and has been, whether or not it is observable or comprehensible...

", and may involve delaying or rejecting relevant action out of concerns for mistakes or faults or appropriateness. Some definitions of doubt emphasize the state in which the mind remains suspended between two contradictory propositions and unable to assent to either of them
(compare paradox
Similar to Circular reasoning, A paradox is a seemingly true statement or group of statements that lead to a contradiction or a situation which seems to defy logic or intuition...


The concept of doubt covers a range of phenomena: one can characterise both deliberate questioning of uncertainties and an emotion
Emotion is a complex psychophysiological experience of an individual's state of mind as interacting with biochemical and environmental influences. In humans, emotion fundamentally involves "physiological arousal, expressive behaviors, and conscious experience." Emotion is associated with mood,...

al state of indecision as "doubt".
Doubt sometimes tends to call on reason
Reason is a term that refers to the capacity human beings have to make sense of things, to establish and verify facts, and to change or justify practices, institutions, and beliefs. It is closely associated with such characteristically human activities as philosophy, science, language, ...


To know much is often the cause of doubting more.

Michel de Montaigne, Essays (Montaigne)|Essais (1588).

If a man will begin with certainties, he shall end in doubts; but if he will be content to begin with doubts, he shall end in certainties.

Francis Bacon, The Advancement of Learning (1605), Book I, v, 8.

Doubt, indeed, is the disease of this inquisitive, restless age. It is the price we pay for our advanced intelligence and civilization. It is the dim night of our resplendent day. But as the most beautiful light is born of darkness, so the faith which springs from conflict is often the strongest and the best.

Robert Turnbull|Robert Turnbull, Life Pictures from a Pastor's Notebook (1857)

Doubt is for the dying.

Imperial Guard, Warhammer 40,000: Dawn of War

To have doubted one's own first principles is the mark of a civilized man.

Oliver Wendell Holmes, Jr., "Ideals and Doubts", 10 Illinois Law Rev 3 (1915).

To rest upon a formula is a slumber that, prolonged, means death.

Oliver Wendell Holmes, Jr., "Ideals and Doubts", 10 Illinois Law Rev 3 (1915). Quotes reported in Josiah Hotchkiss Gilbert, Dictionary of Burning Words of Brilliant Writers (1895).

Doubt comes in at the window when inquiry is denied at the door.

Benjamin Jowett, p. 195.

Doubt indulged soon becomes doubt realized.

Frances Ridley Havergal, p. 195.