How can I change the two figure behavior with my MacBook Pro (6,2)'s trackpad?

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http://askubuntu.com – By default on mac os, with two fingers I can do this: -leave a finger on the mouse pad, and move another finger, and still be able to move the mouse -two finger scrolling requires both fingers be moving this is handy, as sometimes (because the trackpad is so large, I leave my thumb on the "button" (or any other fingers depending on how I'm sitting) for clicking, as clicking AND moving the cursor at the same time is difficult with this track pad (the whole thing needs to be pressed to click) I think this probably also affects click and drag, as I would only be allowed to use one finger, inst (HowTos)