Fix typo

Author: tom-bop

episodes/23.md

@@ -6,7 +6,7 @@ title: Teaching Abstraction: Brent Yorgey
 
 _05/17/18_
 
-Brent Yorgey is a professor of math and CS at Hendrix College. He studys functional programming in Haskell, type systems, and category theory, and more. He is the creator of the [diagrams](https://byorgey.wordpress.com/2014/01/17/diagrams-1-0/) vector graphics Haskell library. He taught [Introduction to Haskell](http://www.cis.upenn.edu/~cis194/spring13/) and [The Art of Recursion](http://www.cis.upenn.edu/~cis39903/) at the University of Pennslyvaia (which were my two favorite classes in college!).
+Brent Yorgey is a professor of math and CS at Hendrix College. He studys functional programming in Haskell, type systems, and category theory, and more. He is the creator of the [diagrams](https://byorgey.wordpress.com/2014/01/17/diagrams-1-0/) vector graphics Haskell library. He taught [Introduction to Haskell](http://www.cis.upenn.edu/~cis194/spring13/) and [The Art of Recursion](http://www.cis.upenn.edu/~cis39903/) at the University of Pennsylvania (which were my two favorite classes in college!).
 
 In this conversation, we talk about Brent's Monad Tutorial Fallacy essay, type systems, FRP, essential vs accidental complexity in Haskell, and the perils of reading academic CS papers and ways to overcome them.