One of the dirty secrets about science is that the process is rarely entirely objective. The road to discovery is littered with judgment calls, educated guesses and assumptions. Some scientists — especially in physics and astronomy — have come to embrace a system of thinking that lays all the subjective laundry out. It’s called Bayesian statistics, and it can guide people not to facts, but to beliefs.
The idea comes from an 18th-century Presbyterian minister named Thomas Bayes, who argued for the possibility of religious miracles at the same time that Enlightenment heroes such as David Hume were making a case for disbelief.
