Great Convention
the forms must be obeyed
The Great Convention was the universal truce of the Imperium, held in place by the balance of power between the Spacing Guild, the Great Houses and the Imperium. Its chief law forbade the use of atomics against human targets, and its rules governed Kanly and the War of Assassins.
The Great Convention was the universal truce of the Imperium, enforced under the balance of power maintained by the Spacing Guild, the Great Houses, and the Imperium. Its chief law forbade the use of atomics against human targets, and its rules set the limits within which the Houses could wage Kanly and the War of Assassins. Each of its rules began with the same watchword: The forms must be obeyed. (Dune)
Purpose and philosophy#
The Great Convention placed strict limits on how the Great Houses could fight their wars and pursue their feuds. Kanly, the formal feud or vendetta, had to be carried on under the Convention's rules and within the strictest limits, and the War of Assassins was the limited form of warfare that the Convention and the Guild Peace allowed. Both channelled conflict into bounded forms rather than open slaughter. Every rule of the Convention began with the same words, The forms must be obeyed, marking it as a code of ritual as much as of law. (Dune)
Provisions#
The Convention rested on the balance between the Landsraad of the Great Houses, the Spacing Guild, and the Imperium. Its chief law forbade the use of atomics against human targets, a prohibition that left the family atomics of the Houses as a deterrent rather than a weapon of open war. By the time of God Emperor of Dune the ban on thinking machines, the commandment that came out of the Butlerian Jihad, is also spoken of as something the Great Convention prohibits. (Dune; God Emperor of Dune)
Tested and bent#
Paul Atreides tested the letter of the Convention at the Battle of Arrakeen. He used the Atreides family atomics to blast a gap in the Shield Wall, and when Gurney Halleck raised the ban, Paul answered that it covered atomics used against people, and he meant to use them against sand. Twelve years into his reign, in Dune Messiah, Fremen conspirators set off a stone burner, an atomic weapon, in Arrakeen on Arrakis, and it blinded him. (Dune; Dune Messiah)
Frequently asked questions
- What was the Great Convention?
- The Great Convention was the universal truce of the Imperium, enforced by the balance of power between the Spacing Guild, the Great Houses, and the Imperium. Its chief law forbade the use of atomics against human targets, and its rules set the limits for Kanly feuds and the War of Assassins.
- Did the Great Convention ban thinking machines?
- God Emperor of Dune links the two: a character there worries that a device might hide a computer and so be prohibited by the Great Convention, recalling the old commandment against making a machine in the likeness of the mind.
- What did each rule of the Great Convention begin with?
- Each rule of the Great Convention began with the words, The forms must be obeyed. The phrase sums up the Convention's insistence that the ritual limits placed on conflict be respected by all parties.
- How did Paul get around the ban on atomics?
- At the Battle of Arrakeen, Paul used the Atreides family atomics to blast open the Shield Wall. When Gurney Halleck worried about the Convention, Paul answered that the ban covered atomics used against people, and he was using them against sand.
Sources
- BookDune, Frank Herbert, Chilton Books, 1965
- BookDune Messiah, Frank Herbert, G. P. Putnam's Sons, 1969
- BookGod Emperor of Dune, Frank Herbert, G. P. Putnam's Sons, 1981
Spotted a factual error or a primary source we missed? Email a correction. Every flagged claim gets reviewed.
Followed from this entry

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Arrakis, known as Dune and later as Rakis, was a harsh desert world in the Canopus system and the only natural source of the spice melange. Home to the Fremen and the sandworms, it became the seat of the Atreides empire and the center of the known universe.

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Paul Atreides
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