So I took the bait.  I thought my Mac might need virus protection after all.  I went ahead and installed Sophos Anti Virus.  I use their Windows products in my office, and I am extremely pleased with them.  I went ahead and installed the Mac client.  Heres where I ran into trouble.  It seems that there is a bug in the software if you have File Vault enabled on your Mac.  Apparently they fight for who loads what first.  Anyway, after you log in to your account on your Mac, the computer just hangs.  I went through a lot of trouble shooting before I figured out Sophos was the culprit.  It took many iterations and tries, but I was finally able to get the software removed.  If you run into this problem, here are the steps to resolve it.  First, reboot your Mac in Safe Mode.  (Press link for how)  Then once logged into your Mac in safe mode, follow these directions to uninstall the Sophos software.  I found that replacing the “su” command with “sudo” worked just fine.