You can only impress yourself if you call yourself names like am a Genius, am the best, am great, because what you think you know might not even be up to 1% of what others know.. That's why most people would say life is divided in to portions and believe me you can't exceed more than that portion you know no matter what you think you know or might have achieved.
Having Seven PhD in different fields doesn't justify that you are the best, because they are people that do have knowledge more than what you think you have, without even holding a PhD to their names. People would say NO MAN IS AN ISLAND OF KNOWLEDGE, I believe this is even big to describe a human because no one can even understand up to 10% of what the world holds nature, water, animals and so on not to even talk of calling the person an Island of Knowledge.
It is true that you might be blessed with knowledge that the world has not seen before but believe me, you don't even know 1/4% of the knowledge the world holds and you shouldn't try to tell yourself you know anything.
No body is an Island of Knowledge And no one can claim that title no matter how many books you have read, things you have seen and places you have gone, you are just a little more knowledgeable than others and nothing else.