From my point of view, differences in intelligence and personality may have genetic causes.There are for example people who suffer from mental disabilities because of genetic problems such as trisomy 21.Yet, apart from a few examples of people whose personality is influenced by genetics, the way people behave and their degree of intelligence originate in their environment.Indeed when you are born your brain is like an empty box and little by little your personality will be moulded by your environment , society will contribute to adding things to this box.How intelligent you become is not determined in advance by your genes.It is something you develop as you grow up.It is the same for your personality.There are values and ideas attached to each society and these ideas are conveyed to you as you grow up.If you live in a family with educated parents who provide you with the opportunity to have a good education, then you are likely to be well educated yourself.Likewise if you live in an environment in which you receive a lot of love and affection you are likely to be able to convey love and affection to people around you. Conversely, if you grow up in a difficult background with non loving parents you are likely to suffer from this lack of affection and it may influence your psychological development in a negative way.Nonetheless, I have to challenge my point of view as regards intelligence. For the majority of people intelligence is something that you improve as you grow up, the more you learn, the more intelligent you will be. However the world provides us with countless examples of people for whom it does not seem to work like that.I allude to the child prodigies whose intelligence capacities are amazing .Obviously these people are endowed with an intelligence which is much more superior to common people like us, so to speak.For them no doubt , genetics is the explanation.Unfortunately for people like you and me, we have to count on our environment.