[S]ince there is an infinity of possible worlds, there is also an infinity of possible laws, some proper to one world, others proper to another, and each possible individual of a world includes the laws of its world in its notion. Gottfried Wilhelm Leibniz
On simple matters we can agree. Water freezes and wood burns. People can agree on social or political issues, though often more from self interest than from reasoned argument.
Agreement is rare or flitting on what is good or bad, worthy or worthless, humane or heartless. Are we simply not wise or intelligent or patient or convincing enough to find consensus?
Agreement is rare because the realm of possibilities is boundless. Every thought or vision carries a cosmos of variations and extensions. A good idea is one that spawns new good ideas, on and on. We are told that God the creator created man and woman in his image: as creators, to be fruitful and to multiply children, and ideas, and worlds.
At first we think that we are the entire world. Then we discover other worlds - things and people - and we think that they are the same as us. Then we discover that they have minds that, like ours, create their own worlds. We learn to communicate with those minds out there. We think that our meanings are their meanings, and this is true for many things, and even for many thoughts. But not for all of them. Then we discover that our deepest feelings are ours alone, and that we have created a continent whose shores are only lapped by waves from distant lands.