"Hello, babies. Welcome to Earth. It’s hot in the summer and cold in the
winter. It’s round and wet and crowded. At the outside, babies, you’ve got about
a hundred years here. There’s only one rule that I know of, babies — God damn
it, you’ve got to be kind.”

— ~ Kurt Vonnegut - God Bless You, Mr. Rosewater

Epic quote here. Yes, to survive in this world, you've got to be kind. This is one aspect you'll have to learn to acquire in your path of life to find happiness.