Writing the lyrics for The Plan was the most difficult of all the lyrics in The Brain because it was to an extant tune that David had in his trunk, written years ago. It was very catchy, and at that point in the writing of the show, he still wanted to write some of the score (he ended up with The Plan and a few measures of The Brain Tap). He'd played the tune for me and I just looked at him as if he were nuts and said, "There's no way to write a lyric for that - it's tuneful, but crazy." The next day I began writing the lyric. Once I had the rhyme scheme (that was the hardest part) then I was able to begin figuring out how to move it along - the half-step rises in the last part are mine, musically, and the tag music "You can kiss this little planet goodbye" is mine, as he couldn't figure out how to end it. He ended up writing three lines of the lyric (in the very last verse - "We have a perfect plan, a plan that's better than, the kind a human would try") - the rest is mine. The rhyme scheme, of course, for the opening section is the last word of the first two lines rhyme, then the last two words of the fourth and fifth lines rhyme (but not with the first two lines' final words) and the last word of the third line and the sixth line rhyme - once you set that pattern, you can't cheat - you have to do it each time. It's tough, but that's what makes it fun.