typo in Level 9 advanced addition world

Stream: new members

[Sailor]

Hi, i think there is a mistake in this sentence R should be in the middle image.png

[Yaël Dillies]

No, because R is a function. R : α → α → Prop, so R x : α → Prop and R x y : Prop. Of course, maths references usually write that x R y, and you could reproduce it here with notation.

[Eric Wieser]

As an example, x = y is really just eq x y behind the pretty-printer

[Sailor]

Ok right !