Cleve Moler, the creator of MATLAB, died a few weeks ago. I've had the opportunity to meet him a few times, and despite him being a genuine mathematical genuis, the thing that impressed me so much was how humble he was, how anti-braggadocious. He was like this in person, privately, and also in public. Moler was an early post-WW2 engineer, his cohort is a shrinking class, and I'm worried about those who are taking their place, and then what happens when my generation and the younger replace them.