Your not grabbing them, that would be a grapple and would provoke an AoO.
How am I tripping them then, with my mind?
You are tripping them, which doesn't require you to get as "close in", you are just hooking one of their extremities.
Neither does the initial grab to start a grapple. You can choose to close in after making the grab. But the grab inself provokes AOO.
The simple fact is that "Trip" is not "unarmed strike" and the trip manuever doesn't provoke an AoO. If it did, it would say so.
They didn't want trip to have a "double jeopardy" of both provoking an AoO and letting you get counter-tripped if you fail.
It is only double jeopardy for those without improved unarmed strike or those not using trippable weapons. Which is what this post was originally about. All of the trippable weapons do less damage then their counterparts, because they can trip. Well if you could just trip a guy with your hand and not use the weapon, then your getting the best of both worlds. I understand this also introduces the risk of being tripped in return, but I believe the designers put in trip weapons, so that non monks could trip without penalty with those weapons alone.
The main point to me is that every other combat manuever in that section goes into detail on when it provokes an AoO. Disarm specifically provokes an AoO whether you do it armed or unarmed. Trip does not provoke an AoO, whether you do it armed or unarmed.
Disarm says you provoke AOO when you do it armed or unarmed because otherwise monks could disarm without provoking an AOO, which of course is unbalancing. Trip doesn't say it invokes an AOO because the book already mentions that melee touch attack provokes AOO if you don't have IUS. Its terrible wording on their part, but there you have it.