As both "yes and no" can't be an answer to one question, so also two captains can be on a ship,because the crew will end up totally confused.
That's also how it is exactly in life, you are either something or not. Life is littered with so many options but one choice.
JUST LIKE;
You either answer yes or no not maybe. Maybe kinda shows confusion .
In a war, there must be a winning side before the war ends. If not, the war has just started.
You are either for a group of people or against them if non, you are a saboteur.
You are either good or bad if non, you should be avoided completely.
You can't be up and down at the same time .That means you are hanging and defying gravity.
You either choose to love or hate someone if non, you are confused.