RES MERAE FACULTATIS
res merae facultatis (rays meer-ee fak-<<schwa>>l-tay-tis). [Law Latin] Scots law. A matter
of mere power.
“Res merae facultatis …. Such, for example, is the right which a proprietor has of building
upon his own property, or which any one has of walking upon the seashore, or sailing upon the sea,
or on any navigable river. It is a right which may or may not be exercised at the pleasure of him
who holds it; and such rights are never lost by their non-exercise for any length of time, because it
is of their essential character that they may be used or exercised at any time.” John Trayner,
Trayner’s Latin Maxims 554 (4th ed. 1894). [Blacks Law 8th]