Thoughts, Logic, and Metalogic

It is in dispute in the literature whether Frege's conception of logic is universalism and whether metalogical questions are understandable and legitimate from the perspective of the universalist conception of logic. In the book, the author argues that despite some apparent challenges, it is fair to attribute universalism to Frege. But since the notion of reinterpretation playing a crucial role in current metalogical investigations is illegitimate from that perspective, given that universalism requires that any theory should have thoughts rather than formulae per se as its subject matter, and therefore that a language in which a theory is formulated must not be reinterpreted, such investigations are illegitimate, not understandable to Frege. But metalogic not involving the notion is not only legitimate, understandable, but also indispensable to Frege's logicist project.