Board Thread:Warhammer 40k General Discussion/@comment-8570919-20130423231429/@comment-3580035-20130426005957

Ummm..... Tau have a miniscule Warp prescence due to their species makeup. What you are implying is that Tau aren't fully sentient, but I think being able to do everything sentient creatures do and more allows them to qualify as fully sentient.

They also didn't become a sentient race 'recently'. Sure, its pretty new in the grand scheme of the universe, yes; but 4 millenia for any sentient race is still a very long time. Its unlikely for them to develop pyskers in the future already because they haven't developed any right now. If the fact that half the Chaos gods were formed during the Dark Ages of humanity (where humans had only been 'sentient' for less than two millenia), then that implies that the human race was psychic from the start. For the Tau, they have not. Ergo, they are highly unlikely to develop psychic powes in the future.

Likewise, Eldar were psychic right from the very beginning because they were made that way. Keeping in mind that the Old Ones were the original psychic race, they simply made another highly psychic race to take on their role when they disappeared. Eldar didn't 'evolve' into a psychic race. They were psychic from the start and haven't changed a bit (in terms of psychic status).