The essence of ethics is
that a thing doing its Dharma (ours) is ethical
and a thing doing other than its Dharma (Adharma) is unethical.
Each conscious entity has an obligation
to cultivate its consciousness
and to open its gateway.
More concrete specifics are handed down
through tradition
or directly decreed
by the gods Themselves.
As explained in basics and in here.
sourceThe great Tao is like a flood
It can flow to the left or to the right
The myriad things depend on it for life, but it never stops
It achieves its work, but does not take credit
It clothes and feeds myriad things, but does not rule over them
Ever desiring nothing
It can be named insignificant
Myriad things return to it but it does not rule over them
It can be named great
Even in the end, it does not regard itself as great
That is how it can achieve its greatness