Listened to Invisibilia: [The Power Of Categories](http://www.npr.org/programs/invisibilia/384065938/the-power-of-categories?showDate=2015-02-06)
Steve Jenkins
February 11, 2015
Steve Jenkins' Journal
The ramblings of Steve Jenkins
Listened to Invisibilia: [The Power Of Categories](http://www.npr.org/programs/invisibilia/384065938/the-power-of-categories?showDate=2015-02-06)