Definition
A Latin phrase meaning "in matters," "in things," or "in cases." Used as a prepositional construction in legal maxims and judicial writing to locate a principle within a particular subject matter or factual context. The phrase most commonly appears in the maxim *in rebus manifestis, errat qui authoritates legum allegat; quia perspicue vera non sunt probanda* — "in clear cases, he mistakes who cites legal authorities, for obvious truths are not to be proved." The maxim expresses a principle of legal reasoning: that invoking authority to establish what is self-evident is not only unnecessary but potentially counterproductive, as over-argumentation can cast doubt on what would otherwise be plain.
Common Language
Modern common usage (Wiktionary): No standard entry. The phrase has no meaningful circulation in modern general English.
Historical common usage (Webster's 1913): Not entered. The phrase belongs to the Latin legal vocabulary, not to common English usage of any period.
The term has no genuine common-language counterpart. Its meaning is entirely bound to Latin legal phraseology, and it appears almost exclusively as a component of maxims rather than as a standalone term.
Why It Matters in Research
Researchers are most likely to encounter *in rebus* not as an independent term but embedded within maxims, particularly the *in rebus manifestis* formulation. Understanding the phrase as a locating construction — "in [such] matters" — is essential for parsing the logical structure of those maxims correctly.
The *in rebus manifestis* maxim carries a practical implication for common law advocacy and judicial opinion writing: courts historically used it to signal that a proposition was so obvious as to require no authority, and sometimes invoked it to dismiss over-cited or over-argued positions as obscuring rather than clarifying. A researcher encountering this maxim in historical case reports or treatises should read it as a rhetorical move, not a rigid procedural rule.
The Coke citation (5 Co. 67a, Jeffrey's Case) anchors this maxim firmly in the early common law tradition. Researchers tracing the use of this maxim in later English and American courts should be aware that the maxim tends to appear in judicial dicta and legal essays rather than as operative legal doctrine. It surfaces most often in discussions of statutory construction, evidence, and the nature of proof.
Because *in rebus* appears almost exclusively within maxim literature, it is largely absent from modern legal indices and search tools unless the researcher searches for the full maxim text. Historical corpus research in Law Mind sources that include Coke's Reports, Latin maxim collections, or early common law treatises is the most productive path.
Historical Dictionary Support
Burrill's Law Dictionary is the sole source in the Law Mind corpus with a dedicated entry, and it treats *in rebus* as a phrase defined by its maxim context rather than as a standalone term. Burrill quotes the full *in rebus manifestis* maxim, supplies the Coke attribution, and adds the explanatory gloss from the report itself: that citing authority for obvious truths "obscures them." This is a concise and accurate representation of how the phrase functioned in classical common law legal literature.
No broader definitional controversy attaches to the phrase. Its Latin meaning is unambiguous. What Burrill and the underlying Coke report preserve is the rhetorical and epistemological principle the maxim encodes — that legal argument has diminishing returns when applied to self-evident propositions, and that excess argumentation signals weakness rather than strength.
Modern legal dictionaries largely omit this term, which reflects its retreat from active legal discourse rather than any change in its meaning.