Thus we find, again and again in history, that epochs of strongly progressive growth of the liberal world of thought, when wealth increases with the development of the division of labour, alternate with epochs in which the principle of violence tries to gain supremacy—in which wealth decreases because the division of labour decays.
The reality of the matter is slightly different : periods in history where the creation of wealth is cheap and easy alternate with periods in history where the creation of wealth is an expensive and difficult proposition. This alternance is always a result of objective conditions, even if it won't necessarily be reducible to them. What people value and what people want have a definite impact on what wealth actually is at any time, but this isn’t an invitation for reformists to “improve” reality through attempting to diddle the mechanisms through which people value and want. It just doesn’t work that way, people adapt to objective reality rather than create it.
And so it is that during the former times the smith and merchant reign supreme, and the crafts of thief and soldier seem undignified occupations, unworthy of the time of a fine young gentleman. As the wheel turns and the latter times take hold the pointless dickery of craftsman and banker fail to command the interest of the fine young gentleman any further, and the bravery and adventure of taking rather than toiling again orient the efforts of [the best of] mankind.
What makes toil more productive than taking, or vice versa ? Mostly, believe it or not, technology. The available technology chiefly decides the tools available to interpret reality - that is to say turn reality into reflections in the mind, which in turn determine the shape and depth of the notions of value. On the other hand the same available technology strictly decides the tools available to manipulate reality - that is to say turn reflections in the mind into reality. The interplay of these two factors results in the ultimate balance between toil and plunder : if a lot can be dreamed but very little made, a lot will be stolen. If but a little can be dreamed but most of it can be made, very little will be stolen at all. Bear in mind that this interplay is in no way linear, and more importantly the two factors aren't linear either.
Technological progress is very far from the monotonically growing function apologists have in mind when they talk of it with their characteristic Skippy the Squirrel wide eyes. Technological progress is more akin to a shadow falling on a complex landscape : as the Sun moves the relative distance between landscape and obstacle may well increase, in which case an impresion of a widening shadow and an increasing depth of knowledge may easily be formed. Just as well however that distance may reduce, in which case the converse'd be true.
In any case as the shadow moves more stuff falls under its empire, tis true, but also stuff that used to be under its empire is no longer. Fifty years ago pretty much any college graduate could use a slide rule, few if any could today. Five centuries ago any woman of age could use a loom, few if any could today. While it's conventionally polite to call those items recently liberated from under the shadow "obsolete", it is nevertheless a fact that they've just escaped our grasp.
The movement of the Sun, the shape of the obstacle and the background being shadowed are all pretty much given. The full revolution is slow enough so that it escapes any systematic attempt at recording ; the movement fascinating enough that few living people actually notice what's going on, with the majority of the population gathered at the "gaining" edge, pushing the shadow outward, to conquer further expanses of previously unshadowed space (were you not aware that people actually discover things ?), with the occasional inattentive bloke accidentally stepping too far outside, into the stark light of the Sun's ridicule (only to be covered by the shadow soon enough - in many cases too late for his funeral however).
The entire illusion works, of course, on the swivel of "what's important", which is a function of what may be understood of what may be perceived. As with any magic act, these are wholly in the hand of the magician, placed there by the unremitting will of the audience. And who's the magician ? Why, the audience itself. A more economical engine could scarcely have been ever devised : it progresses all by itself, in a box on a shelf.
At least this way things don't get too boring. Do they ?