Science and Religion (Rule 4)

4) Any true religion must specifically encourage scientific inquiry without limitation.
This is in accordance with the other 3 laws (it's true, it's consistent, it's complete). As stated earlier a true religion would never fear honest inquiry, and therefore would encourage investigation as such could only prove the truth.

I add this as a law for a specific reason. In my historical studies I've noticed a tendency for any religion, no matter how much it claims to support science, to enter a period where it opposes science. Christianity began this way, not only discouraging scientific study (bringing advancement to a halt for a few centuries) but ultimately set back the state of knowledge to pre-helenic times.
Islam, during the western worlds dark age very much encouraged scientific advancement. Today however most islamic countries have regressed and it is only through globalism that they do not fall behind.
Asian nations (especially China) have had a unique advantage with no real religion (Confucianism is a doctrine for living and organizing society but is not a religion) and no real "dark age" though their systems (and communist government) have delayed much scientific inquiry until changes made in recent years.

It is in fact religion which has held back man kind more then anything else in history. Without the dark ages setting us back, we'd be millenia ahead of where we are now. Considering the increasing rate of scientific advancement, it's difficult to imagine just how far along we'd be.