## Episode 018 - SCS Conference: Peter Koellner, Andrew Sicree

As I've mentioned, we batch recorded the last four episodes about a month ago, and so we opened with a retrospective on the conference as a whole and its significance.

We moved on to discuss Peter Koellner. Koellner was the next talk and probably deserves his own podcast. I have gotten his lecture slides from him but won't have time to analyze them for a few weeks. The short version for now is that he gave us some perspective on Godel's theorem, a result in mathematical logic that many (including many agnostics like the physicist and mathematician Roger Penrose) have taken to imply that human thought must transcend any finite logical system that could be, say, programmed into a computer: in other words, the human mind is not a computer. Koellner argued, in large part from Godel's own writings, that what he actually proved is probably that EITHER human thought transcends the mechanical OR that there are mathematical truths that transcend mind. This is potentially a blow to a number of people who rely on the argument to prove our superiority to our own machines, but I myself find either conclusion to be exciting.

Andrew Sicree was next. He gave this tremendously gung-ho talk about Father Nick Steno, the 17th century member of the founder's club of geology (I think that's fair; Sicree basically called him the founder, singular). It was mostly fairly familiar stuff to me, some of which I have lectured on myself in classes in passing. He is still known today for Steno's Laws of stratigraphy (i.e., the relative ages of rocks):

Principle of Superposition

Principle of Original Horizontality

Principle of Inclusions

and in mineralogy he is remembered for the Law of Constant Interfacial Angles, basically the very dimmest beginning of crystallography. However, Sicree gave some time to other aspects of Nicolaus Steno's thought and also to his career as a layman and cleric. I only thought I was a Nick Steno fan before this talk. Andrew Sicree is the real deal.