Physicists have thought experiments, economists have models. In each case they present an initially simplified model to make a tentative argument which may then be elaborated as variables are added back in. Me I am a medievalist. And a mythologist. And we pose our thought experiments and models in a slightly different form: the fairy tale. So here goes:
Once upon a time there was a land called Merrie Olde Angle-Land. It looked a great deal like medieval England, just simplified and viewed through a golden glow. But just because Angle-Land is fictional doesn't mean that a story about it doesn't illustrate some truths about the parallel historical kingdom of England. On the other hand readers shouldn't interrupt the story with notes that "Well gee, field systems and social organizations were different in medieval Kent, what do you say about that!?" Just this: well that is England, this story is about Angle-Land and an Anglish historical and economic and social environment that is derived from but not identical to its English counterpart. So let's recommence:
Once upon a time there was a land called Merrie Olde Angle-Land. At the time of our story it was some seven centuries remove from an invasion of the Engle-Exxons who had slaughtered or driven out the previous Keltic-Romish inhabitants (after asking them for names of certain rivers and cities). The Engle-Exxons were a race of free Germanic peasant-warriors who while having a native aristocracy and ruled by kings organized their daily and yearly routines via a rude democracy consisting of male householders who held local courts and a yearly Witangemoet to settle such things as taxation. (on the other side of the Anglish Channel, the Frankels called it a 'parlement').
After the conquest of the portion of Keltic-Romish Brittia they would call Angle-Land, the Anglish divided the fertile regions into 'hides', each consisting of enough arable (i.e. plougable) land and associated woods, pastures and meadows to support a free peasant 'family'. As a side note the Anglish 'family' was not typically either the modern nuclear family or a Mediterranean style multi-generational family led by the oldest surviving male but instead a 'household' headed by a 'hus-bund' and 'wif' (our modern 'husband and wife') and including minor children and often one or more dependent/retired parents of the hus-bund or wif plus a handful or less of house and farm servants often enough the young adult children of neighbors who had yet to marry and establish their own 'family' in their own household. But on this perhaps more in later chapters.
The 'hides' as originally established in Angle-Land consisted uniformly (unlike England where the variety was bewildering) of 120 acres of arable distributed thoughout a large 'open' field itself divided into three parts to facilitate what was known as 'three course' farming. In this style of farming each field would be in a different stage of the growing cycle, one ploughed/seeded/sprouting, a second in full growth/being readied for harvest, and a third lying 'fallow' or unploughed at any time in that year. And here we have our first implication for labor exploitation: in any given year only 80 out of every 120 acres even gets ploughed, and only 40 acres in any given ploughing season (meaning there are two). As we will see in the next chapter or so this has large implications for the typical work week.