The internet is overflowing with memes and jokes after President Trump referred to himself as a "stable genius" on Twitter yesterday. The remark was part of a thread meant to defend his mental stability in the wake of the drama surrounding Fire and Fury, Michael Wolff's critical look at the Trump presidency. Responses ranged from fact-checking in nature, to... well, a predictable abundance of horse jokes. Even stars such as Mindy Kaling and former White House staffer Kal Penn had to get in on the fun.