There can be no good
Without bad

There can be no light
Without dark

There can be no happiness
Without sadness

But isnt it funny how there cant be a positive without a negative, yet the negative seems to be heavier...?
Humour me

It is better to be good, or for something to be good
That would be, well good.
So to balance out the good, there must be equal bad, right?
'cept the bad outweighs the good you see. Bad is heavier and overshadows the good.

Bad > Good

It is preferable for there to be light
Light is in a generalistic sense, a good thing.
So to balance out all the light, we must also have the dark
'cept once again, the dark overshadows the light. The darkness is worse than the light and presents itself as a heavier presence.

Dark > Light

Last but not least, oh ** **... Happiness, it is the greatest thing,
Thus it is a very good thing.
But to balance out the happiness, sadly there must be sadness, and sadness is one of the heaviest emotions because it outweighs the good, the light and the happiness by so much, the happiness is almost non-existent

Sadness > *Happiness