# dormitive virtue

idiom

Source: https://englishreference.com/idiom/dormitive-virtue
Updated: 2026-08-10

## Meaning

A type of tautology in which an item is explained in terms of the item itself, only put in different (usually more abstract) words.

## Examples

- Explaining sleep by calling it a dormitive virtue explains nothing.
- He uses a dormitive virtue when he says the machine works because of its power.
- The scientist criticized the theory as a dormitive virtue because it defined the process using the very term it tried to explain.
- The professor argued that saying people are poor because they lack wealth is a dormitive virtue that fails to address the actual causes of poverty.
- When you claim a drug works because it has healing properties, you are just using a dormitive virtue instead of explaining the chemistry.
- By attributing the sedative effect of the medicine to a dormitive virtue, the author merely restated the observation without providing any genuine scientific insight into the underlying mechanism.

## Origin

A calque translation of Latin, virtus dormitiva, coined by Molière in The Imaginary Invalid. In the play, he lampoons a group of physicians providing an explanation in macaronic Latin of the sleep-inducing properties of opium as stemming from its "virtus dormitiva".

---

From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.