Piket: I want to start with marks, because i, as you do point out, piket's book is a in some sense, there's certainly a wink, if not a nod, to marks the title of his book is capital in the 20 first century. And mark's book, of course, was called das capital a. He certainly sees himself in that tradition, that grand tradition, not just focusing on capital, but also in deriving general rules. So i thought it be useful for me and for our listeners, to hear what were mark's general rules and what went wrong with them.