Have you ever witnessed the anger of the good shopkeeper, James Goodfellow, when his careless son has happened to break a pane of glass? If you have been present at such a scene, you will most assuredly bear witness to the fact that every one of the spectators, were there even thirty of them, by common consent apparently, offered the unfortunate owner this invariable consolation – "It is an ill wind that blows nobody good. Everybody must live, and what would become of the glaziers if panes of glass were never broken?"
Now, this form of condolence contains an entire theory, which it will be well to show up in this simple case, seeing that it is precisely the same as that which, unhappily, regulates the greater part of our economical institutions.
Suppose it cost six francs to repair the damage, and you say that the accident brings six francs to the glazier's trade – that it encourages that trade to the amount of six francs – I grant it; I have not a word to say against it; you reason justly. The glazier comes, performs his task, receives his six francs, rubs his hands, and, in his heart, blesses the careless child. All this is that which is seen.
But if, on the other hand, you come to the conclusion, as is too often the case, that it is a good thing to break windows, that it causes money to circulate, and that the encouragement of industry in general will be the result of it, you will oblige me to call out, "Stop there! Your theory is confined to that which is seen; it takes no account of that which is not seen."
It is not seen that as our shopkeeper has spent six francs upon one thing, he cannot spend them upon another. It is not seen that if he had not had a window to replace, he would, perhaps, have replaced his old shoes, or added another book to his library. In short, he would have employed his six francs in some way, which this accident has prevented.
"It is never an advantage to have one’s plants destroyed by shells or bombs unless those plants have already become valueless or acquired a negative value by depreciation and obsolescence. ... Plants and equipment cannot be replaced by an individual (or a socialist government) unless he or it has acquired or can acquire the savings, the capital accumulation, to make the replacement. But war destroys accumulated capital. ... Complications should not divert us from recognizing the basic truth that the wanton destruction of anything of real value is always a net loss, a misfortune, or a disaster, and whatever the offsetting considerations in a particular instance, can never be, on net balance, a boon or a blessing."
Cost of opportunity should be
the sort of thing that government officials lose sleep over (or pretty much anyone, when it comes down to it), because any use of resources is in detriment of a use in another area, because, you know, there is scarcity of resources and all that
And this frame of thought can be applied from the most menial to the most important of decisions:
*Do i eat junk food and live life being overweight? How will i have to compensate for it? Does eating junk food cost me too much to buy other things or actual healthy food?
*If i went to university instead of working, how long until i make a profit from the hypothetical money i could be making at work?
*If i spend overtime on a hobby that makes me have less hours of sleep, is it worth it for overall health?
*What are the costs of enforcing a law that punishes poor people instead of devoting it to social programs?
*What are the human costs when only monetary efficiency are taken into account?
(Im out of steam here, see if someone else can connect the dots better that I)