Things which are found within the reason of a law are supposed to be within the law itself.

Explanation

(English-origin maxim — no Latin equivalent; the English title is the original form.) Whatever falls within the spirit and purpose of a law is governed by it, even if not expressly named — a statute prohibiting fraud covers schemes not specifically enumerated if they fall within the mischief the law was enacted to remedy.

Where this applies

• A statute prohibits the sale of adulterated food, and the court holds that selling food contaminated during packaging falls within the law even though packaging is not specifically mentioned, because it falls within the law's reason.
• A law forbids fraudulent misrepresentation in real estate, and the court applies it to a seller who omitted material facts, because omission in this context is within the spirit of the prohibition.
• A regulation bans dangerous driving, and the court holds that reckless operation of a motorboat on a public lake falls within the rule because the reason behind the law — protecting public safety — applies equally on water.