I believe this paper by Marcus ( https://arxiv.org/ftp/arxiv/papers/1801/1801.00631.pdf ) earlier this week inspired this.
Edit: I don't mean Marcus inspired the term differentiable programming; he inspired LeCun to emphasize the wider scope of deep learning after Marcus attacked it. In fact, LeCun liked a post on twitter rebutting Marcus' paper that also talks about differentiable programming: https://twitter.com/tdietterich/status/948811917593780225