One of my favorite Profs from undergraduate days.
I don't know if I already thought different or if I was just ready to hear Tim Allen's mind blowing ideas. In any case, when I was introduced to complexity science the ideas felt familiar and comfortable. Tim was teaching complexity before there was a name for it. This five minute video is worth watching, he understands the use of visuals, and even with only his hands as props, it helps to see how he illustrates some of the concepts.