I've given 100s of talks over my career, but yesterday was t... 22 Aug 2013 2013-08-22 2013-08-22 I've given 100s of talks over my career, but yesterday was the 1st time I was brought to tears by what followed: http://t.co/u2XGRA1thv 1

I've given 100s of talks over my career, but yesterday was t...

I've given 100s of talks over my career, but yesterday was the 1st time I was brought to tears by what followed: http://t.co/u2XGRA1thv