Someone who has a great personality, and you can talk to him about almost anything. He can be complicated to figure out, and a guarded person, but once you get to know him properly you realise how amazing he really is...he is so much better than what he sees in himself, and will only reveal the best side of himself to certain lucky people!
He is intellectually very gifted, and will be willing to pass his cleverness on to others which is one of his most admirable gifts! Most notably, he will be generous in passing on mathematical knowledge.

Now see example...

When you eat dirt for the first time and leave your family to build a shack in the woods