You can really feel it in the production of infrastructure and to a lesser extent in the production of tools and equipment: the really dense and heavy stuff, meant to persist, takes incredible energy and work to manipulate. Moving the heavy stone, shoveling gravel, moving dirt, manipulating steel, iron, and lumber - in these activities the energy transferred from the body is easy enough to detect. One makes enormous exertions, and then as soon as one comes to rest, the deep ache, the fatigue, the ceaseless hunger is palpable and dramatically affects the consciousness, but those very things can lend a deep satisfaction of their own as they are addressed with deep rest, and the pots of chili, curry rice, sausages, hamburgers, medleys of potatoes and onion and cabbage, and what have you, taste all the more delicious, and fill the holes and cracks.
Besides, the difficult and strong exertions can produce lasting effects enjoyed by many: perhaps a century or more for good solid infrastructure, well done. And for the ancients we can talk millennia, at least in terms of the remaining bones still standing in those haunted historical monuments. Though we shall see how long our quality steel and iron constructs last, and of course the stone and brick built to endure. And there is always the question of who is building what for whom.
Us hypermoderns have become accustomed to the belching and squirting out of plastics, which erupt and cool into slick and colorful shapes, which then begin to crack and flake and photodegrade and melt away nearly as soon as they are instantiated, but not completely disintegrating a moment before they are temporarily appreciated and then bought, after which they can then proceed to fall apart; the perfect material for a society of marketers and conmen. It teaches: nothing lasts, nothing is to be trusted.
For things to really endure, it does take quite a bit of time and energy to put into something, at least in my experience. That feeling that something challenging really took a bite out of you and knocked you down for a bit, is, contrary to initial impressions, a reassuring and satisfying feeling, so long as you can be confident that what you are doing is worthwhile.
With all fairness to plastic, we could say all of that chemical and technical knowledge is a deep and enduring work of its own, all of which of course rests on a dense and solid infrastructure, but the concentration and nature of the labor varies wildly in its geographical and temporal spread, and who is doing the laboring and why and who is benefitting from the labor, and then there is the matter of whether the project itself is worthwhile or even sustainable, a loaded question for most people anyway. Bah, another set of arguments for another time.
