The mind and the immune system have been shown to be intimately linked, and scientists are consistently finding that doing good deeds benefits one' s immune system. The bone marrow and spleen, which produce the white blood cells needed to fight infection, are both connected by neural pathways to the brain. Recent research has shown that the activity of these white blood cells is stimulated by beneficial chemicals produced by the brain as a result of magnanimous behavior. The statements above, if true, support the view that ["magnanimity is beneficial to one's own interests", 'the number of white blood cells will increase', 'magnanimous behavior can be regulated by the presence or absence of certain chemicals in the brain', 'lack of magnanimity is the cause of most serious illnesses']