Yes we knw Unity is d key, working with one mind is all we need to achieve d great,greater & d greatest success in life, but don't u tink dat will be too easy & life won't be interesting anymore? No just imagine no more fighting, stealing, killing, corruption, envying, strife, competition etc... believe it or take it without those mention above life will be so boring..!!and will quickly come to an end.. I will say God put all these in place to make life worth living for and interesting also to distract us(Man) from getting to Heaven the easy way and that is exactly what happened after the flood...see Gen 11:1-8