“Constitution is both a matter of fact and a matter of law”. Who is the author of it?

A.V. Dicey, the influential British constitutional theorist, articulated this dual character of constitutions in his work 'Introduction to the Study of the Law of the Constitution'. By 'matter of fact', Dicey meant the actual political practices and conventions that operate in practice, while 'matter of law' refers to the formal legal rules and judicially enforceable provisions. This distinction between 'constitutional conventions' (political facts) and 'constitutional law' (legal rules) is central to Dicey's framework.