oh it technically adds up tot he point of this : if a man destroys the ye out of a gentlemen eye they shall destroy his. If he destroys a eye of a commoner he shall pay one mina of silver. if he destroys a eye of a commoner he shall pay half of the price of a slaves price. Basically they put the punishment to be sort of fair each punishment depended on the type of class you were in. Like gentlemen were important so the price was high and slaves were low in society so there punishment were low. and for the commoners there price a little bit higher han the slaves but lower than the gentleman class.