The Theory of Abstract Objects

The Theory of Abstract Objects
Edward N. Zalta has been working on the theory of abstract objects.
Many of the key ideas come from the work of Alexius Meinong.

I strongly recommend the introduction to The Theory of Abstract Objects
to be found at
The Theory of Abstract Objects


(Disclaimer: Zalta and I have collaborated before, and are collaborating again now.
My point of view is anything but unbiased.)