The knowledge argument, or the Mary's room thought-experiment, as elaborated by Robert Stalnaker.
If our experience of colour can be seen as yielding no contingent facts about the world, what might our awareness of such an experience entail?
What could it mean to say that phenomenal properties just are constituents of our knowing something?
Considered comments are welcome. I haven't made up my mind on this one yet.
![](https://i.ytimg.com/vi/DZzIH8D_THQ/mqdefault.jpg)