I once was on an elevator with Richard Stallman at MIT with my 14 year old son. He turned to my son and asked him what OS he used. My son replied 'Windows', b

I once was on an elevator with Richard Stallman at MIT with my 14 year old son. He turned to my son and asked him what OS he used. My son replied 'Windows', because it's free. Stallman might have lost his mind at this point, but instead smiled and said 'Windows isn't free and free software isn't free'. This post reminds me of that exchange.