Nationalism is an infantile disease. It is the measles of mankind.
The science of the mind can only have for its proper goal the understanding of human nature by every human being, and through its use, brings peace to every human soul.
Humans have certain properties and characteristics which are intrinsic to them, just as every other organism does. That's human nature.
The main scourge of humanity is not ignorance, because the ignorant often have excuses, but the refusal to know.