Basic rules of science
Every science has been based on a number of basic features or basic facts that cannot be proven further.
They all are obvious, self-evident, (almost) needless to say.
In mathematics people call them axioms,
in science it is about postulates and
in religion they talk about dogmas.
In mathematics: 3 + 5 = 5 + 3,
in science: action = reaction and
in religion: God exists.
Many people think you cannot reason in religious matters.
That is a wrong concept.
As in all other sciences you should initially believe in the basic rules.
Once accepted you can reason perfectly.
So basically all sciences are a kind of believe.
If one of those basic rules is refuted all consequences derivated from it turn invalidate and dissapear.