Gamp's Law of Elemental Transfiguration

• Type: Law of Magic, Elemental Transfiguration
• Owners: Not Applicable
• Maker: Gamp

As a magical law, Gamp's Law of Elemental Transfiguration has no physical form. It is a fundamental, governing principle of magic, specifically within the advanced field of Transfiguration. The law delineates the boundaries of Conjuration, establishing that while a skilled witch or wizard can create, or conjure, a vast number of objects and substances from thin air, there are specific, defined things that cannot be created ex nihilo (from nothing). These are known as the five Principal Exceptions to Gamp's Law.

The primary function of Gamp's Law is to define the absolute limits of Conjuration. While many inanimate objects can be conjured at will, the five Principal Exceptions represent categories of items that are impossible to create magically from nothing. Of these five exceptions, only one is explicitly identified in the original novels.

• 1. Food: It is impossible to conjure food. As Hermione Granger explains, “no one can” produce food out of thin air. However, magic can still be applied to food in other ways:
  • It can be summoned from a known location using a Summoning Charm like Accio.
  • The quantity of an existing food supply can be magically increased, as Mrs Weasley is known to do.
  • It can be transformed or cooked using magic.

The other four Principal Exceptions are never explicitly named in the novels. It is also understood that certain concepts and items, while not necessarily one of the five formal exceptions, are impossible to magically create, such as love and life. It is also impossible to conjure genuine money, as it would be detectable as fake and would destabilize the wizarding economy.

The law is named for its creator, the wizard Gamp, though no further details about him or the circumstances of the law's discovery are provided in the novels. The law is first and only mentioned by name in Harry Potter and the Deathly Hallows. In 1997, while on the run and hiding from Lord Voldemort's forces, Ron Weasley complains about their lack of food. Hermione Granger cites Gamp's Law to explain why she cannot simply conjure a meal for them, despite her considerable magical talent. This reveal establishes a critical limitation that adds to the trio's suffering and desperation during their hunt for Voldemort's Horcruxes.

Gamp's Law is a crucial piece of world-building, serving to ground the magical system of the Harry Potter universe with concrete rules and limitations. It prevents magic from being a limitless solution to all problems, thereby introducing stakes and driving the narrative. During the Horcrux hunt, the law's prohibition on creating food directly impacts the plot. It forces Harry Potter, Ron Weasley, and Hermione Granger to resort to scavenging and relying on meager supplies, adding a layer of mundane hardship and realism to their quest. This constant deprivation fuels the tension within the group, contributing significantly to Ron's frustration and his temporary abandonment of Harry and Hermione.

• J.K. Rowling has stated that the other four exceptions are not love, life, or information. She noted that one can conjure a facsimile of a living thing, such as an Inferius, but not a true being with a soul. (J.K. Rowling interview)
• Rowling also confirmed that while money is not one of the five Principal Exceptions, it cannot be conjured from nothing. Any magically created gold or currency would be worthless, as the Goblins who run the wizarding economy have means of detecting counterfeit currency, which is why the Philosopher's Stone was so uniquely powerful. (J.K. Rowling interview)
• The precise identity of the remaining four Principal Exceptions remains a popular topic of fan discussion and theory.