I think “externalities” is close to the concept I want to capture with the second dimension, but I want to bake this concept into the pricing model in such a fundamental way that it can’t be ignored. Suppose the second dimension of price in my thought is an approximation of the “total external cost” — this metric undergoes market and actuarial optimization but the domain in which these barks are traded reflects a different set of overall constraints than are captured by the inflationary dollar monetary system. As a rough example, let’s say the inflation model for the “bark” currency is tied to the total number of tree years on the planet (I don’t think this would be the right way, but just trying it as a conceptual example). So there are roughly num_tree_years “barks” in existence growing at something approaching num_trees per year. Lets say as more trees are planted or time passes that every human is allocated a proportional share of “barks” commiserate to the “bark” growth rate (or loss rate if trees are cut down faster than they are growing). So the currency reflects an externality in a shared way that is also quantitative ... if someone wants to cut down an old growth forest to build a car park, they are gonna need to find a lot of people willing to loan them “barks” to pay for it as they will have to compensate the global balance for all the barks they remove — in addition to seeking the traditional investors who will loan them money for construction on the traditional basis of their sense of the likely desirability-profit of the parking garage ...

This “barks” toy example is definitely not the precise idea I want to capture and not at all fully fleshed out — but suppose a more developed version where there is a mechanism for estimating the externality costs of any transactions and where there are different rules that apply when paying for the “externalities cost” vs paying for its dollar price ...

I think it's an interesting concept. As I think about it, we already have a weak version of this in the form of lobbying and political organizing. If a company wants to destroy an old growth forest to build a parking lot, in many areas they need permits / zoning etc. People who would suffer if the forest were destroyed -- people who live nearby, environmentalists, etc -- can raise money and lobby, or organize politically, to make their case, as can those who would benefit -- the company building the parking lot, maybe some neighbors who value more parking more than they value the environment.

I think the issue with this system is that generally the groups imposing the externality are more organized, and often wealthier, than the groups who suffer from it (tragedy of the commons again). Getting the trees cut down may be priority #1 for the company, and opposing it might be priority #30 for a few hundred people. Priorities that low are effectively zero, since most people dont even have time to handle their important priorities

I feel like your idea could potentially tip the balance in the favor of the "commons" by imposing a higher upfront cost to the creator of negative externalities, but I can't really put my finger on whether that is true.

Very interesting! Though I wasn't watching closely I think I saw a real-world example of your concept on (I think) BBC News yesterday. Forgive me if this is not wholly accurately retold:

It was about about unsustainable fishing on a large trawler that could set out about a million fishing hooks a day, and catching everything.. large tuna, sharks, etc. They then projected globally; this is the dominant way we go about fishing, and with it halfway this century our oceans will be empty of fish.

Then they brought the example of - I believe - Irish fishermen, who some years ago and seeing hugely diminishing returns, decided on a different system whereby scientists would determine beforehand the minimum shoal size that would lead to sustainable growth of the fish population. The fishermen would then be free to catch the remainder of the population, and divide it amongst themselves based on stake in the game.

This 'share' determines their yearly quota. If next year the total shoal population had grown, their 'share values' had increased. This modern fishing method apparently worked perfectly, and every year they have bigger returns, catching almost as much as in 'old times'.

An important example would be a family with children where both parents could work but do not have to. From the GDP POV, it is a huge boost to have a second parent earning an income, even if most of the additional monies end up dedicated to the costs of outsourcing some parental duties. A stay at home parent might be producing as much or more value to the family, while not contributing to the GDP at all.