Scientists work on the basis of "what we know" because from a practical point, you can't work off a foundation of what you don't know. When pushed, all scienti

Scientists work on the basis of "what we know" because from a practical point, you can't work off a foundation of what you don't know. When pushed, all scientists will admit "based on current understanding". This is what makes a "breakthrough" revision of understanding so exciting! It doesn't happen every day!