MLSys showed how systems can accelerate AI. The next shift is broader: AI is beginning to reshape the practice of systems itself. This emerging paradigm, which we call system intelligence, goes beyond automating programming tasks. It enables new forms of reasoning, design, validation, and evolution for complex systems while preserving rigor. In this talk, I will argue that system intelligence changes not only what systems we can build, but also how we understand systems as a discipline. It pushes us to rethink systems principles and methodology, shifting attention from code-level complexity to greater rigor in specification, design, and validation. Through our experiences with system verification, I will discuss how this shift may help give systems a stronger scientific foundation.