Only your nose knows what a nose can know because there's no nose but a nose, so that nose can only know what a nose knows but noses don't know anything, cause they're noses, ya' know?
"A riddle", could be a valid solution, as riddles often state,"I (am)... what am I?". Sentient could also be a solution, as it means آپ are self aware, hence:"I know what I am". Also, "An oxymoron", could be valid, as it is a statement that contridicts itself: clearly stating what it is (I know what I am), yet leading آپ to سوال its nature (What am I?). In short, there are many solutions. My سوال is: Which one are آپ looking for?