Your mind is the key, and yes we have heard the similar phrase over and over. But how much we have know our own mind, with it's trick and it's own denial?
The world would not change, nor the society, if you don't change yourself first. And you would not change, until you know who you really are. But before you know who you really are, only after you accept all the darkness and light within yourself, you could understand - perhaps - your inner self.
It - always - starts within.