This C/P pretty much tells the story on the smarts of Cruz.

After graduating from Princeton, Cruz attended Harvard Law School, graduating magna cum laude in 1995 with a Juris Doctor degree.[4][41] While at Harvard Law, he was a primary editor of the Harvard Law Review, and executive editor of the Harvard Journal of Law and Public Policy, and a founding editor of the Harvard Latino Law Review.[35] Referring to Cruz's time as a student at Harvard Law, Professor Alan Dershowitz said, "Cruz was off-the-charts brilliant".[42][43][44][45] At Harvard Law, Cruz was a John M. Olin Fellow in Law and Economics.[46]

Cruz currently serves on the Board of Advisors of the Texas Review of Law and Politics.[47]