Infants lack the verbal capacity to give us feedback on their sensations and perceptions, but we can measure their abilities by monitoring bodily functions. If doctors monitor a newborn and find increased heart rate, increased blood pressure, increased stress hormones, and decreased oxygen in the blood, which sensation can they surmise the infant is experiencing

Pain

Explanation:

Bodily functions are often a response to the sensation being felt by an individual, when an individual is relazlxed and in a good mood, the function of several body Organs are quite different from when such individual is undergoing a painful sensation. Therefore, Bodily functions are employed when evaluating the state or sensation which is occurring to an infant as they lack the ability to verbally express their feelings. Therefore, an infant whose Bodily functions exhibits increased heart rate, increased blood pressure, increased stress hormones, and decreased oxygen in the blood could be said to be undergoing pain.

People had no choice. If you were born into peasantry or serfism, you were there for life unless you became a priest. You couldn't fight the king or the lords or knights. The kings got a ton of power and no one could do anything to stop it. The only people with enough power to not allow it to happen were the kings and they didn't want it to stop.  It is much like how the 1% in USA is getting way richer and more powerful because we, as the middle class, can't do anything about it.