Wait! Cancel my last post! In exploring the virtual environment, I was struck by the existence of an executable *pip *in the virtual environment's "bin" directory. So I tried again to install BeautifulSoup, but this time I got a very different error message. This pip couldn't find BeautifulSoup, unlike the module I had been using. (My python3.6 installation does not include a command-line executable pip).
So I reissued the command, this time giving it the name of the module,"bs4". And this time, pip found and installed beautifulsoup (note the lowercasing) into my virtual environment! Thanks for your help. -- https://mail.python.org/mailman/listinfo/python-list
