I _Really_ Don't Know

A low-frequency blog by Rob Styles

Intensional and Extensional Sets

One of my collegaues called the other day and asked if we still relied on the distinction between intensional and extensional sets (really intensionally and extensionally defined sets). Yes, even more so now. from Intensional and Extensional Sets.

If you don't know the difference (I didn't) then it's worth reading.