A precise and perspicuous specification of mathematical domains of computation and their inherently related type inference mechanisms is a prerequisite for the design and systematic development of a system for symbolic computing. This paper describes Formal, a language for giving modular and well-structured specifications of such domains and particularly of “mathematical objects”. A novel framework for algebraic specification involving so-called “unified algebras” has been adopted, where sorts are treated as values. The adoption of this framework aims also at being capable of specifying polymorphism, unifying the notions of “parametric” and “inclusion” polymorphisms. Furthermore, the operational nature of the specification formalisms allows a straightforward transformation into an executable form.