Equation 1 · Part 8 · Water Before Demography
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What this part means
Capital delta attached to a quantity marks a difference between two values of that quantity; the article’s sign convention determines the order.
Its job in the formula
Capital delta attached to a quantity marks a difference between two values of that quantity; the article’s sign convention determines the order.
Full expression→change→Article meaning
The passage around this formula
For most of the period in which Europeans kept parish records, the largest towns buried more people than they baptised. Population still rose, which means the arithmetic was closed from outside. The identity is trivial but it is worth writing down, because almost every disagreement in this field is a disagreement about one of its terms: . Population change in a city equals natural increase, births minus deaths, plus net in-migration. The urban graveyard claim is the specific and testable assertion that for long stretches the first bracket was negative while the sum was positive: cities grew, and grew only because the countryside kept sending replacements.
Learn the underlying idea
Addition combines quantities; subtraction measures the signed difference between them. Parentheses show what is combined before the rest of the expression is evaluated.
Open the illustrated addition and subtraction in an equation guide →
Sources cited in the article section
- [1] Mortality, migration and epidemiological change in English cities, 1600-1870 ↗
- [2] Natural Decrease in Early Modern Cities: A Reconsideration ↗
- [3] The Urban Mortality Transition and Poor-Country Urbanization ↗
These citations provide research context; check each source for the exact claim it supports.