The new tax bills for Tisbury Great Pond properties were a shocker all right. The camp that I co-own with my three siblings, as the Sturgis Family Trust, was valued at $2,123,800 in fiscal year 2007. Now, with no effort on our part, it’s supposedly worth $4,419,700. For years we’ve been managing to pay the taxes — $9,568 in fiscal year 2007 — by renting the camp out most of the summer. The new tax bill, $17,511 and change, means renting for nine or ten weeks with no margin for error: no cancellations, and nothing left over for maintenance either. Selling looks more and more like the only way out.

The valuation says we can get almost $4.5 million for a scant four eroding acres. Wow! It’s like hitting the lottery! We could make enough money to support ourselves in the style to which none of us are accustomed, or want to become accustomed to, and in the process leave our neighbors — whose families we’ve known for more than 40 years (my family didn’t arrive on the pond until the mid-1960s) — in a worse lurch than they’re in now. So the values go up some more, the pressure to sell increases, and in a few years Tisbury Great Pond is ringed with big houses that are occupied two or three weeks a year by people whose involvement in Island life is minimal. Say that these absentee owners throw up locked gates and security systems so that yet another method of informal pond access dries up. Say that these owners pay as little attention as they can to the ecology of the pond. Who wins? More to the point, who loses?

Have I stumbled into cloud-cuckoo-land or what? We’re being strong-armed into selling not by any nefarious developer with dollar signs in his eyes but by a mechanical formula that says these not-quite-four acres and a rustic, off-the-grid camp are worth $4.5 million. The land was bought circa 1970 and the camp built for less than $50,000. A few short years ago I was weirded out by the realization that I co-owned a property worth more than a million dollars. Now it’s four times that. Why can’t I retire? Why can’t I afford a house?

Because, of course, the valuation is in cloud-cuckoo-land dollars: funny money that only materializes when the property is sold. Nevertheless, the tax on this funny money has to be paid in real money by Feb. 1.

When are we going to get it through our heads that all those meetings, ordinances, master plans, districts of critical planning concern and other devices beloved of conservation commissions, planning boards and the Martha’s Vineyard Commission are useless if attention isn’t paid to what the market is doing to undermine our best efforts? The market is a lousy long-term planner. Over the decades the market has brought us such wonders as planned obsolescence, strip mining, strip malls, currency speculation, hedge funds, outsourcing and pollution out the wazoo: all of which benefit some (or even many) people in the short term but lead to disaster if allowed to continue unchecked. On the Vineyard, never an easy place for working people to live, the market has created such a yawning gap between income and housing costs that lifelong and longtime residents continue to leave — not because they want to, but because in practical terms it’s crazy to stay. And those of us who are crazy enough to stay pay a price too: working more hours and more jobs to pay the rent or the mortgage, and thus having less energy and less time to do the myriad unpaid things that keep a community going.

The current system of assessment and taxation is a key part of the problem. The only value it acknowledges is monetary value. It can’t deal with anything that doesn’t come with a price tag attached, and if it can’t find a tag, it’ll go to cloud-cuckoo-land to find one. Those affected by the drastic increase in Tisbury Great Pond valuations are lucky: none of us is threatened with the loss of our primary residence or livelihood. But the assess-and-tax machine threatens neighborhoods too: taxes on longtime residents’ homes go up when people with big bucks take a fancy to the area, build and move in. When actual selling prices follow the upward valuations, the character of an area changes, and often in ways that don’t satisfy anyone. If the only way to pay the rent or the taxes on Main street is to sell T-shirts or jewelry or cappuccino and oversize cookies, only a saint or a crazy person would do anything else. And anyone who values the rural character of the Island would do well to consider how an emphasis on cloud-cuckoo resale value affects agricultural prospects. Thimble Farm was recently saved for community-supported agriculture by the last-minute arrival of a buyer who could pay the seller’s price and wasn’t driven to seek a strictly monetary return on his investment. Yet another close call, and this time the community won.

So can this assess-and-tax machine be curbed, and perhaps pointed in a different direction? Sure, but only if its human operators — legislators, planners, town officials and, ultimately, we the people — choose to take responsibility for monitoring the machine’s operations and making modifications as needed. In the case of the properties on Tisbury Great Pond, and in any neighborhood or town where big money starts throwing its weight around, the problem is the widening chasm between valuations in cloud-cuckoo-land money and taxes that have to be paid right now in 2008 dollars. What if a baseline valuation were established and taxes paid on that, with increases pegged to a town’s total valuation? When one or a few sales force the hypothetical resale value of everyone’s property into cloud-cuckoo-land, then the taxes are due only in cloud-cuckoo-land money: they aren’t converted to real money until the property is sold in an arm’s-length transaction. Think about it. It could be that one smart tweak of the machine is worth a thousand bylaws.

Susanna Sturgis lives in West Tisbury.