I'm ready then to start finally the... the work on Volume Four.  But it still isn't out, right, so... so what's happening? Well, in fact, about 400 pages of it are... are out now in paperback and it takes... takes me more than a day a page this... now... I'm not able to... I'm not able to convince myself to... to settle for just reproducing things that I find in my files but every time I look at something I see that there's a chance to improve it, and that takes me another few days. So I'm... I'm adding a lot of material that doesn't appear in... in the literature as I'm writing the... as I'm writing the Volume Four. I can't sustain that either I know but the parts... I tell myself that the parts of the book I'm writing now are so fundamental that... that they're different from the parts that will follow and that next year I will just be putting together things that... that are... are not very highly original. But, in fact, the... like tonight I'll be finishing the index for... for a... for a new section and this is about 60 pages and... and out of the 60 pages I think they're, you know, well, 15 pages of it is stuff that hasn't appeared in the literature and... and quite a few different ideas are there, and the same in the... these 400 pages of Volume Four that have come out, I... I can't resist going beyond the sources that I... that I see when it's such a fundamental part of the subject. So I'm not the... at the rate I'm going it's... it's pretty clear that I won't I finish, you know, the whole project until I'm 90 years old. So, even though I'm not putting on, you know, I'm not going beyond the table of contents that I jotted down on that day in January 1962 when... when I was asked to write a book on compilers, I... I still have sort of that table of contents, and I'm... this... the field has grown dramatically and there's... there's so much good stuff I can't resist putting in. The... let me see... so that's... that's my life right now, pretty much going through my files for... for Volume Four. All the things I'm... I'm reading, I keep on reading more things in the library but then that suggests ideas that I put... that I put together and I contact people around the world for their help in... in trying to debug the ideas and... and to check that I got... that I got things straight. And hopefully I'll be able to continue this for a long time. It's fun because I get to put together the work of authors that didn't know about each other's work, so then can... then I get a chance to make a natural connection between... between those things and I love to... to find a way to present material. I... I know that I'm getting to be an old man now and so my... my style isn't as... as sprightly as it used to be when I'm young but I still have the... the 3000 pages of manuscript I wrote in the '60s that I can use those... those sentences to make... to keep a little bit of youth in there. Still I know that the material is not an easy read, people will maybe keep it in the bathroom or something like that or they'll have the book on their shelf just to prove that... that... just to imply to somebody that they could understand it. The subject is not... there's no Royal Road to some of this material, some of it is inherently difficult but pretty much I'm enthusiastic about the way things are going. When I... like this morning I was making the index and I see parts that I... that had to struggle with when I wrote but now when... then they come out it looks like... it looks like a good story that I didn't... and the struggle, the fact that I was struggling with it doesn't seem too obvious to me now.