Did norman malcolm write a book about wittgenstein?

…the point of the book is ethical. I once wanted to give a few words in the foreword which now actually are not in it, which, however, I’ll write to you now because they might be a key for you: I wanted to write that my work consists of two parts: of the one which is here, and of everything I have not written. And precisely this second part is the important one. For the Ethical is delimited from within, as it were by my book; and I’m convinced that, strictly speaking, it can ONLY be delimited in this way. In brief, I think: All of that which many are babbling I have defined in my book by remaining silent about it.