For example, observations may tell that more of a chemical compound exists than previously thought possible.
Cosmological observations tell us the standard model explains about 4% of the energy present in the universe.
"There are so many things only direct observation can tell us," Montoya said.
His observation probably told him as much about the current situation as Ariel already knew.
What is more, they add, simple observation tells them that their children have thrived there.
Only observation will tell if there is one possible biochemistry, or many.
My own observation of human nature told me that this was wisely said.
The solar observations he made would have told him he was off.
"However, theory is theory, but observations might tell us something different," he said in an e-mail message.
Sometimes observation can even tell you when to cut your losses.