Very kind words from Brantley and Clem. It's an interesting notion to regard Unix as gestational until it came out in public talks (1973) and was exported to universities.
Maybe I could claim to have laid the groundwork for Unix by causing Multics to be written in PL/I, a language big and sprawling, like the project itself. That unintentionally provided plenty of stimulus for thinking small. Ken was absolutely on his own when he began to fiddle with building a tiny operating system on the GE 645. I heard about it only after the fact.
After Multics, I ran interference to keep our once-burned higher management from frowning too much on further operating-system research. I was aware that Ken, Dennis and Rudd were discussing the subject down the hall from my office, but I did not participate in the discussions. At the same time, I was noodling over what would later be called shell pipelines; but I did not come up with the vivid term "pipe" or a halfway workable syntax for another three years. While these actions may have contributed to a welcoming environment for Unix, they in no way "started" it.
Doug