Acceptable use of proprietary software

[Fred Phillips]

For my physics course (AS Advancing Physics from the IOP), we are
required to use a piece of proprietary MS Windows software called
Folio Views. I have written a series of emails to the IOP asking
for a free alternative, but they just told me to “use WINE, other
people do”. I _have_ to use this software to be successful in my
course, which is quite important. This led me to the question: where
do others feel that using proprietary software is acceptable to them?