[rational_indian]

I don't think this is a sound argument. How does it demonstrate attention being not equivalent to time? At best it shows the professor's attention / time / money can be wasted by dull students. Was this ever under dispute?

[julienreszka]

What was under dispute is whether time is the only real currency. I say it is not and I say it's attention that is the real currency because that's what you really allocate.