This is my next move, on the left side, played on the star point. I play here to claim the left side in answer to Dan's move 7, following the proverb corners, side, then center. My next move depends on where Dan plays and then we get to fighting. 

Black Move 9, H17 - H17 extends the influence from L17. By no means does this move guarantee territory, but it's good shape, and divides Doc's two groups. As the proverb says, the third line has special powers. However, another proverb says that the third line is life, the fourth line is victory. So, we'll see how Doc responds to this.