Does a prohibition entail the invalidity of what is prohibited?

هل النهي يقتضي فساد المنهي عنه؟

A question of legal theory: when the Lawgiver forbids a sale, a marriage or another act that produces legal effects, does the prohibition show that the act is invalid, that is, that its effects do not follow? Al-Ghazali in al-Mustasfa sets out three views: the great majority hold that it entails invalidity; some distinguish what is forbidden in itself from what is forbidden for something else; and he chooses the view that it does not entail invalidity, answering four arguments of its proponents. The book's editor notes that al-Ghazali here departs from al-Shafi'i's known position.

Summary

A question about prohibition in legal theory: when the Lawgiver forbids a sale, a marriage or another act that produces legal effects, does the prohibition entail that the act is invalid? Al-Ghazali treats it in the third pole of al-Mustasfa. ¹

What al-Ghazali means by invalidity

By invalidity al-Ghazali means that the effects do not follow from the act and that it ceases to be a cause producing them. ² His view rests on the point that prohibition contradicts obligation and permission but not the forbidden act's being a sign that ownership or lawfulness has arisen: there is no contradiction if the Lawgiver says "I forbid you divorce during menstruation in itself, but if you do it your wife is separated", or "I forbid you to slaughter another's sheep with another's knife without leave, but if you do, the meat is lawful"; the contradiction would be to say "I forbid it and permit it". ² So prohibition does not show invalidity by language, since the Arabs may truly forbid lawful causes, nor by the law unless evidence from the Prophet ﷺ establishes that prohibition is meant to invalidate, and the issue is proving such evidence. ³

The views

The editor notes in his study that al-Shafi'i held that prohibition entails invalidity, that al-Ghazali here chose against his imam's view, and gives this as an example of his independence from any school. ⁴ ⁵

The opposing arguments and al-Ghazali's replies

Al-Ghazali lists four legal arguments of his opponents, among them: what is forbidden is bad and a sin, so how can it be lawful? He answers that if "lawful" means commanded or permitted, that is impossible and he does not claim it; if it means being a sign of ownership or lawfulness, that is the very point in dispute, and it is not impossible for divorce to be forbidden and yet made a cause of separation, nor even for prayer in a usurped house to be forbidden and yet made a cause of discharging the obligation. ³ ⁶ Another: a prohibition of sale or marriage comes only to show that it no longer transfers ownership; he replies that this is the point in dispute, and that many sales and marriages were forbidden yet remained effective. ⁶ Another is the hadith "every act not in accordance with our affair is rejected", to which he answers that "rejected" means not accepted as obedience and devotion. ⁶

Opinions on the question

The question: Does a prohibition of a contract or act show that it is invalid?

First opinion · Sunni tradition (the museum's frame) · Sunni: the great majority, as al-Ghazali reportsMain reference

a prohibition entails the invalidity of what is forbidden; the editor notes that this is the view of most Shafi'i, Hanafi and Hanbali jurists and the Zahiris, and, from al-Qarafi, of the Malikis. ¹

More opinions (2)

Sunni tradition (the museum's frame) · Sunni: some, as al-Ghazali reportsMain reference

if the act is forbidden in itself the prohibition shows invalidity; if for something else, it does not. ¹

Sunni tradition (the museum's frame) · Sunni, Shafi'i: al-Ghazali's choiceMain reference

it does not entail invalidity; the editor notes that this is the view of al-Qaffal, the Imam al-Haramayn, many Hanafis and a group of Mu'tazilis including al-Karkhi, the judge Abd al-Jabbar and Abu al-Husayn al-Basri, and observes that al-Ghazali framed the question for sales and marriage, so that it would be accurate to say his view is invalidity in worship but not in transactions. ¹

Sources

al-Ghazali, al-Mustasfa min Ilm al-Usul, vol. 3 (study and edition by Hamza ibn Zuhayr Hafiz) , p.199

al-Ghazali, al-Mustasfa min Ilm al-Usul, vol. 3 (study and edition by Hamza ibn Zuhayr Hafiz) , p.200

al-Ghazali, al-Mustasfa min Ilm al-Usul, vol. 3 (study and edition by Hamza ibn Zuhayr Hafiz) , p.201

al-Ghazali, al-Mustasfa min Ilm al-Usul, vol. 1 (study and edition by Hamza ibn Zuhayr Hafiz) , p.77

al-Ghazali, al-Mustasfa min Ilm al-Usul, vol. 1 (study and edition by Hamza ibn Zuhayr Hafiz) , p.78

al-Ghazali, al-Mustasfa min Ilm al-Usul, vol. 3 (study and edition by Hamza ibn Zuhayr Hafiz) , p.202

Unattested interest (al-maslaha al-mursala, istislah)

An interest for which no specific text of the law testifies either for or against. In al-Mustasfa al-Ghazali makes istislah the fourth of the 'supposed sources', dividing interests by the law's testimony into those it confirms (which reduce to analogy), those it cancels (void), and unattested ones, which are open to reasoning; he defines interest as preserving the law's purpose in protecting religion, life, intellect, progeny and property, allows acting on an unattested interest at the level of necessities when it is necessary, certain and universal, and holds that it is not a fifth source but returns to the Book, the sunna and consensus.