Self-evidence is a sentiment of immediate certainty about a state of things; when expressed, the corresponding statement is obvious, that is, it does not require justification, and should be accepted as such, S. Dismissal.

The term aperception is used to designate this form of knowledge as produced by a conscious perception, and accompanied by reflection. Knowledge by aperception is opposed to knowledge by inference, and therefore to knowledge acquired through argumentation, which is a kind of inference. Three kinds of aperception, that is to say three main sources of evidence, can be identified and distinguished form one another:

— Self-evidence as the fruit of the divine revelation of a transcendental reality.
— Perceptual self-evidence of sense data.
— Intellectual self-evidence given by intuition.

The simplest way to legitimate an assertion is to invoke one of these three sources, S. Argument-Conclusion.

The certainty manifested in a direct, simple affirmation corresponds to the certainty associated with aperception, S. Repetition:

Pure and simple assertion, kept free of all reasoning and all proof, is one of the surest means of making an idea enter the mind of crowds. The more concise an affirmation, the more destitute of every appearance of proof and demonstration, the more weight it carries. The religious books and the legal codes of all ages have always resorted to simple affirmation. Statesmen called upon to defend a political cause, and commercial men pushing the sale of their products by means of advertising are acquainted with the value of affirmation.
Gustave Le Bon, [The Psychology of the Crowd]. [1895][1]

Inferential argumentative belief might be considered inferior to belief based on any kind of evidence: this observation is at the root of the paradoxes of argumentation.

1. Dogma: Revelation as a source of certainty

Believers consider the revelation gathered in the sacred books as a source of certainty. This revelation, which took place in the sacred time of the origins, can be renewed by a particular revelation, such as that which Blaise Pascal has described in what is now called his Memorial, producing an immediate and absolute “certitude”:

The year of grace 1654,
Monday, 23 November, feast of St. Clement, pope and martyr, and others in the martyrology.
Vigil of St. Chrysogonus, martyr, and others.
From about half past ten at night until about half past midnight,
GOD of Abraham, GOD of Isaac, GOD of Jacob
not of the philosophers and of the learned.
Certitude. Certitude. Feeling. Joy. Peace.
GOD of Jesus Christ.
My God and your God.
Your GOD will be my God.
Forgetfulness of the world and of everything, except GOD. […]

Pascal, Memorial. [2]

2. Self-evidence of the sense data

The direct physical perception of a state of affairs immediately legitimates a claim. There is no need to argue to see and claim that the snow is white. As the adage says “facts are the best arguments”; the question “Is snow white?” is not debatable (“a-stasic”, S. Stasis; Evidentiality).

From the philosophical point of view, Descartes has rejected the possibility of founding knowledge on sense data by the hypothesis of the “evil genius” (Descartes [1641], First Meditation).

3. Intellectual intuition

Descartes accepts only intellectual intuition as a source of certainty:

Rule 3 – Concerning objects proposed for study, we ought to investigate what we can clearly and evidently intuit or deduce with certainty, and not what other people have thought or what we ourselves conjecture. For knowledge can be attained in no other way. (Descartes [1628], Rule 3)

“Good intuition” is infallible:

By intuition I mean, not the wavering assurance of the senses, or the deceitful judgment of a misconstructed imagination, but a conception, formed by unclouded mental attention, so easy and distinct as to leave no room for doubt in regard to the thing we are understanding. (Id, Rule 7).

This intuition is that which makes us accept something as “beyond reasonable doubt”. So for example, we can feel fairly certain that by taking a point out of a line one can draw a single second line parallel to this line; or that the square of any negative number is positive. These certainties have been called into question by the construction of imaginary numbers and non-Euclidean geometries.

4. Consequences

4.1 Conflict between sources of evidence

It may seem that the most incontestable kind of self-evidence is the direct evidence provided by sense data. Yet the following text shows that it may be judged inferior to that emanating from the authority of the sacred text. It must be noted that the author’s concluding commentary ratifies this hierarchy.

The first disagreement among the Companions after the death of the Prophet concerned the reality of his death itself. After the Death of the Prophet, ‘Umar ibn al Khattaab, may God be pleased with him, insisted that the Messenger of God did not die, considered any such talk a false rumor spread by the hypocrites, and threatened to punish them for it. This went on until Aboo Bakr appeared on the scene and recited the verse of the Qur’an:

Muhammad is no more than a Messenger. Many were the Messengers who passed away before him. If he died or were slain, will you then turn back on your heels? Whoever turns back on his heels, not the least harm will he do to God; but God [on the other hand] will swiftly reward those who [serve him] with gratitude’ (3: 144).

And another verse of the Qur’an:

‘Truly you will die [one day], and truly they [too] will die [one day]’ (39: 30).

When ‘Umar heard these verses his sword fell from his hand and he himself fell to the ground. He realized that the Prophet, may God bless him and grant him peace, had passed away and that the divine revelation had come to an end. […]

Differences over the Prophet’s Burial […] These were two critical issues [about “the reality of the death of the Prophet” and about “the burial of the Prophet”], which were swiftly resolved simply by resorting to the Qur’an and the Sunnah.
Taha Jabir al ‘Alwani, 1993, The Ethics of Disagreement in Islam, p. 35-36.[3]

4.2 Subtracting from doubt

The argument, the basis of the argumentative derivation of a conclusion, is presented as being above doubt. It is conveniently framed as an aperceptive datum, that is to say as something which is as certain as a revelation, as sensible evidence, or intellectual intuition. It follows that the person who refuses to share this data will be considered, as disgraced, infirm or idiotic. It is therefore not necessary to refute him or her, since he or she is already defamed, S. Destruction; Dismissal.
Extended argumentability assumes that any person can be summoned to account for his or her beliefs, and that he or she must justify them, so that it is illegitimate to postulate any kind of a priori certainty. This thesis is difficult to apply to points of view which are considered certitudes of a religious order, such as “there is no God but God”; mathematical, “the square of a positive number is positive”; or simply everyday arguments such as, “I believe that the ground will not collapse under my feet”, S. Dialectic. Self-evidence can be opposed to extended argumentability, S. Conditions of Discussion

[1] Gustave Le Bon (1895). La Psychologie des Foules. Paris: Alcan. Quoted after Gustave Le Bon,The Crowd. A Study of the Popular Mind. New York: Macmillan, p. 126.

[2] Quoted after (07-09-2017).

[3] Taha Jabir al ‘Alwani, 1993, The Ethics of Disagreement in Islam. Herndon: VA: International Institute of Islamic Thought, p. 35-36. Quoted after: