Which early mathematician built one of the first mechanical devices to automate the process of addition?

Blaise Pascal

Explanation: For years historians considered the inventor of the first mechanical calculator to be the French mathematician, philosopher, and apologist Blaise Pascal (1623-1662). To assist his father's work as a tax collector, the 19-year-old Pascal created a mechanical device that performed simple addition and subtraction.

which time period is this? or is this story fictional, i'm going to need more info to answer this question

the noble might have thought that the system was far because they had lot of things and riches and the serf would have thought that the feudal system was un fair because of the way they were treated.