There is considerable interest today in the use of blockchain technology to provide better visibility into shared information among a number of participants and systems arranged in a decentralized peer-to-peer topology. Several challenges in blockchain technology remain to be addressed, including the interoperability, survivability, and manageability of blockchain systems. Crucial to answering these challenges is the need to understand aspects of the Internet architecture that has made it scalable, resilient, and a commercial success as a global connectivity infrastructure. In this paper, we discuss a design philosophy for interoperable blockchain systems, using the design philosophy of the Internet architecture as the basis to identify key design principles. We recast some of the challenges faced in the design of the Internet architecture to that of the design of an interoperable blockchain architecture. We emphasize interoperability as a crucial requirement for the survivability and manageability of blockchain systems. The goal is to define an interoperable blockchain architecture, in which common components of the blockchain architecture can begin to be standardized, leading to lowering of development costs, better reusability, and higher degree of interoperability.