Well, something like "privileges" seems like a design that is a holdover from a time of shared computing. We've adpated it for other uses, and for some people

Well, something like "privileges" seems like a design that is a holdover from a time of shared computing. We've adpated it for other uses, and for some people it's become some sort of security religion. If we assume it exists for the purpose of protecting users of the same computer from each other, it has no need to exist in most cases. Computers are affordable enough that we can all have our own. There is rarely necessity to share computing time. Plan 9 settled the issue. But sometimes I think some people have come to love the mental challenge of UNIX permissions. It is like a game to them. I made a function that produces all possible permissions for a file, including the nonsensical ones, so I could display permissions as octal instead of the usual ls format. Have you ever thought about how many possibilities there are? Too many. The setuid concept is interesting and must have seemed quite innovative at the time. Doesn't surprise me they filed a patent for it. But today, I could just as well do without the complexity.