Imagine being shown N samples of random variables drawn independently
from the same distribution. What can you say about the distribution? I
n general, of course, the answer is nothing, unless you have some prio
r notions about what to expect. From a Bayesian point of view one need
s an a priori distribution on the space of possible probability distri
butions, which defines st scalar field theory. In one dimension, free
field theory with a normalization constraint provides a tractable form
ulation of the problem, and we discuss generalizations to higher dimen
sions.