User blog comment:Sbiis Saibian/Introduction to Googology/@comment-2600:8800:800:700:D185:FB0A:EC4E:A546-20180321030813

"The largest number humanity will invent by the year 1,000,000,000 C.E." If you claim that THIS is your number ... then you've just triggered the Barry Paradox again. Because you see, then this number has already been invented in the year 2014 C.E. Damned circular references!

But this is what Rayo's number does too. And numbers like Rayo's. They say "a number so big that it takes a googol (or more) symbols to describe it". But they just ended up describing it with about 50 English letters. So... does it take a googol symbols or just 50 letters? If that future number can't be allowed, then Rayo's number can't be either.