"One of history’s fews iron laws is that luxuries tend to become necessities and to spawn new obligations." Sapiens, By Yuval Noah Harari
This quote stood out for me when I read Sapiens.
This quote stood out for me when I read Sapiens.
Separately, tendency can mean a type of outcome is more likely, or that there is an underlying force acting in a direction, regardless of whether that force is cancelled by other forces.
And so "tend" and "iron law" are interpreted as assertions of different levels of certainty, where "tend" implies a certainty greater than 50% and "iron law" a certainty closer to 100%.
Not really. Tendency denotes a general inclination, such as objects tending to move toward the centre of mass. Tectonic plates tend to shift slowly. In both cases these are very solid and reliable predictions which are almost certainly true in a vast majority of cases.
I would not agree with the statement vis-a-vis luxury items and necessity (fur coats, diamond rings, harems, are not demanded by all), but there is a tendency for certain classes of items to be considered "essential" over time.