What’s the appropriate attire for learning?

Enclothed Cognition. There is certainly evidence to say that what you wear not only affects how you are perceived but also affects your own performance. A neat little summary can be found here http://wmbriggs.com/post/5353/

I assume that the Professor's call for a return to 'historic standards of decency' refers to a time when universities didn't include women, given that the academic 'uniform' that he refers to is one exclusively worn by privileged men. Indeed, one wonders after reading this piece whether there are any women at all at the Universities of Notre Dame and/or Oxford - either as staff or students - given none are mentioned or even acknowledged here.