The Index Finger allows you to gauge how a person feels about themself. It is a reflection of their self-confidence.
To check out your partner, look at the childhood hand. (The left if they are right-handed; the right if they are left-handed.)
This is the hand that directly registers how they felt about themselves as a child. Check out the length of the index finger.
Then, to see how they have dealt with life, look at the index finger on their dominant hand. About half of the born-shy population have a longer index finger on this hand. These persons, depending on their looks, character traits and efforts, have gained confidence by the adult years.