Abstract. Inductive and coinductive types are commonly construed as ontological (Churchstyle) types, with canonical semantical interpretation. When studying programs in the context of global ("uninterpreted") semantics, it is preferable to think of types as semantical properties (Curry-style). A purely logical framework for reasoning about semantic types is provided by intrinsic theories, introduced by the author in 2002, which fit tightly with syntactic, semantic, and proof theoretic fundamentals of formal logic, with potential applications in implicit computational complexity as well as extraction of programs from proofs.Intrinsic theories have been considered so far for inductive data, and we presently extend that framework to data defined using both inductive and coinductive closures. Our first main result is a Canonicity Theorem, showing that the global definition of program typing, via the usual (Tarskian) semantics of first-order logic, agrees with their operational semantics in the intended ("canonical") model. The paper's other main result is a proof theoretic calibration of intrinsic theories: every intrinsic theory is interpretable in (a conservative extension of) first-order arithmetic. This means that quantification over infinite data objects does not lead, on its own, to prooftheoretic strength beyond that of Peano Arithmetic.