What Does "Mutatis Mutandis" Mean?

The Latin phrase mutatis mutandis uses two forms of the Latin verb “to change” to affect a meaning that could be translated as “by change making necessary changes” or “all necessary changes having been made.” It is used in various scholarly and legal disciplines to talk about implementing a set of changes. The phrase generally leaves the reader or listener to contrast two various statements or scenarios, or to provide different final forms for a document.

In its technical structure, the phrase mutatis mutandis uses a perfect passive participle and a gerundive form to provide the above meaning. In a shorter translation to English, it could be represented as “changed changes” or a similar reiterated verb. Regardless of the translation, many professionals understand it as an effective way to refer to changing either a theoretical or a concrete statement or set of statements.

Hypothetically, someone might say “mutatis mutandis” to alternate between a scenario that doesn’t have a certain condition, and another one that does. For example, if someone referred to all existing speed limits being lifted in a certain jurisdiction, they might say, relative to the current situation; “mutatis mutandis, drivers would go a lot faster.” This kind of hypothetical statement is a popular use of the term.

Another major use of the phrase is for the redaction of a document, not to hide sensitive information, but to reflect a set of given changes. A professional editor might write “mutatis mutandis” to indicate that a set of names, dates, or other facts would be changed consistently throughout the document. This use of the phrase can be thought of as the human equivalent of a “search and replace” command for a word processor or other software. It governs a global change or set of changes for a given target.

In modern systems, this phrase will often be changed into English or another language. Instead of using mutatis mutandis, many officials find it easier to communicate to a mass audience through such translated phrases as “by making all of the above changes” or “considering that the above were in effect.” Others, though, might use the term as a piece of professional jargon, either to elevate themselves above an audience unfamiliar with Latin terminology, or as a regular habit, for example, learned through a long career in academia.