More often than not,being short stacked (10X the big), I would call it, seeing it as the best opportunity to double I will likely see. He has gone allin from mid/late pos with 1700 chips. If he had one of the two hands that dominate you - aa or kk - he probably does not push. He likely holds AK, AQs or a mid pocket pair. That means you got almost a sure coin toss to double up. This is an inflection point in the tourney, and I do not think you can afford to throw it away. The only exception, IMO, is if you have some specific info on him that he only pushes with aa or kk -- not likely.