exceptio probat regulam de rebus non exceptis
Latin phrase
ex·cep·tio pro·bat re·gu·lam de re·bus non ex·cep·tis
| \ eks-ˈkep-tē-ˌō-ˌprō-bät-ˈrā-gu̇-ˌläm-dā-ˈrā-ˌbu̇s-ˌnōn-eks-ˈkep-ˌtēs
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Definition of exceptio probat regulam de rebus non exceptis
: an exception tests the rule as to things not excepted
also
: an exception can demonstrate that the rule exists