"Well, Glaucon, this term "paleo" is more elusive than it at first
seems..."

You are right, Todd.  "Paleo" can be elusive.  I believe, though, that we
can determine if a particular food, such as peanuts, is paleo by asking
the following question:  Is it part of a class of foods consumed by our
forebears where that consumption was both regular enough and long enough
to allow adaptation?  It's not necessary, for instance, that we consumed
cows for hundreds of thousands of years for cow meat to be healthy.  Cows
are a particular in the class of large game and are therefore healthy.  (I
won't get into the grassfed vs. feedlot debate here).

So are peanuts paleo?