In Empire Strikes Back Yoda comments "This one a long time have I watched. All his life as he looked to the future, to the horizon, never his mind on where he was! What he was doing!" (Likely not an exact quote) So my question is... by what medium could Yoda watch over Luke? I know after becoming one with the force some Jedi have this ability, but how is that possible when still alive? Is it a similar connection to the force that caused Luke to forsee his friends pain at Bespin? Or Yoda and Obi-Wan sensing extinguished lives from so far away?