"Math" is a human invention much the same way "Time" is a human invention. We measure it, we describe it, we manipulate it on paper- but It was always there.

So are ethics.

"Ethics" are man-made, but unlike time and mathematics, they do not exist without man. Time and mathematics are tools we created to understand our world; ethics is a code we created to tell us how to live in it.

Ethics exist in the animal kingdom "without man". Some animals mate for life. Some animals protect each other from harm, even putting themselves in danger.

Ethics are an abstraction that reflect the realities of entity interaction. The reason these abstractions are useful is the same reason that numbers are useful as an abstraction that represents quantities of objects.

The tie of ethics to reality isn't as easy to see as numbers, but when you realize that ethics are practical and evolved as a survival mechanism, maybe you can begin to see the connection.

Can you elaborate on "the same way"? I thought most people would agree that math is not a product of human brain, it exists regardless of the existence of human race.

Depends on the math in question. I don’t really believe that the real numbers, for example, correspond to a physical phenomenon. They’re just a convenient tool we use to solve problems.

Right. Ethics exist without the human race as well. Like math, they parallel reality but are thought of as conceptual.