Is Eywa a fungal organism?

[Human No More]

Originally Posted by Tiberius

No . Eywa does not work like the human brain, and there is nowhere in the film where anyone says this. Eywa displays abilities which appear supernatural, such as foreknowledge of the future (for example in the way she chose Jake). Although Eywa has a physical component, she also has a spiritual component. In an Interview James Cameron described Eywa as an "encompassing Spirit"

There's nowhere it says that.
Grace describes the structure very well, and there was no demonstrable knowledge of the future - or otherwise, why not prevent the destruction of Hometree and the tree of voices? or even the RDA's arrival on Pandora? Why not just blow up the ISVs if Eywa really is some kind of mystical superbeing as you seem to think?