Stevie Wonder Lawsuit -- You're Blind, But You're Not Deaf!

Stevie Wonder knew full well what he was doing when he signed an agreement to pay his attorney's widow 6% of his royalties because it was read out loud to him ... according to the widow.

As we've reported ... way back in the day Stevie signed off on the deal with Johanan Vigoda -- but Stevie thinks the wool was pulled over his eyes, and he's filed a lawsuit over it.

Now, Vigoda's widow ... Susan Strack is calling BS on Stevie. She says Vigoda had a witness read the entire contract to Stevie -- including the part where she would continue to get her husband's 6% fee, even after he died.

In her legal docs, Strack acknowledges Stevie came back years later and contested the contract, but never got it done before Vigoda died. Her point is ... even though Stevie doesn't like it, the contract is still binding.

Translation: Go kick rocks. And pay me while you're doing it.