A few days ago, after a furious argument, I was thrown out of a wood where I have walked for more than 20 years. I must admit that I did not behave very well. As I walked away I did something I haven't done for a long time: I gave the gamekeeper a one-fingered salute. In my defence, I would plead that I was overcome with unhappiness and anger.The time I have spent in that wood must amount to months. Every autumn I would spend days there, watching the turning colours or grubbing for mushrooms and beechmast and knapped flints. In the summer I would look for warblers and redstarts. I saw a nightjar there once. It is one of the few peaceful and beautiful places in my part of the world that's within a couple of miles of a station: I could escape from the traffic without the help of a car. Part of me, I feel, belongs there. Or it did.It is not that I wasn't trespassing before. Nor has the status of the land changed: it is still owned, as far as I know, by the same private estate. No one tried to stop me in those 20-odd years because no one was there. But now there is a blue plastic barrel every 50 metres, and the surrounding fields are planted with millet and maize. The wood has been turned into a pheasant run. Having scarcely figured in the landowner's books, it must now be making him a fortune. And I am perceived as a threat.The words that rang in my ears as I stomped away were these: "You've got your bloody right to roam now - why do you need to come here?" It struck me that this could be a perverse outcome of the legislation for which I spent years campaigning: that the right to walk in certain places is seen by landowners as consolidating their relations with the public. All that is not permitted will become forbidden.But this, I expect, is a secondary problem. The more important one is surely the surge of money foaming through the south-east of England. A thousand woods can be filled with pheasants and still there are not enough to serve the people who have the money required - the many hundreds of pounds a day - to shoot them. We were told that the rising tide would lift all boats. But I feel I am drowning in it.Two weeks ago, writing in the Financial Times, the economist Andrew Oswald observed that "the hippies, the greens, the road protesters, the downshifters, the slow-food movement - all are having their quiet revenge. Routinely derided, the ideas of these down-to-earth philosophers are being confirmed by new statistical work by psychologists and economists." As I qualify on most counts, I will regard this as a vindication.Oswald's point is that the industrialised countries have not become happier as they've become richer. Rates of depression and stress have risen, and people report no greater degree of satisfaction with their lives than their poorer ancestors did. In the US, the sense of wellbeing has actually declined. One of the problems is that "humans are creatures of comparison ... it is relative income that matters: when everyone in a society gets wealthier, average wellbeing stays the same."The same point has been made recently by the New Economics Foundation and by Professor Richard Layard in his book Happiness. New developments in psychological testing and neurobiology allow happiness to be measured with greater confidence than before. Layard cites research that suggests that it peaked in the UK in 1975. Beyond a certain degree of wealth - an average GDP of around $20,000 per head - "additional income is not associated with extra happiness". Once a society's basic needs and comforts have been met, there is no point in becoming richer.I am astonished by the astonishment with which their findings have been received. Compare, for example, these two statements:"So one secret of happiness is to ignore comparisons with people who are more successful than you are: always compare downwards, not upwards." Richard Layard, 2005."It put me to reflecting, how little repining there would be among mankind, at any condition of life, if people would rather compare their condition with those that are worse, in order to be thankful, than be always comparing them with those which are better, to assist their murmurings and complainings." Daniel Defoe, 1719.We have been led, by the thinking of people such as the psychologist John Watson and the economist Lionel Robbins, to forget what everyone once knew: that wealth and happiness are not the same thing.Comparison is not the only reason the professors of happiness cite for our failure to feel better as we become richer. They point to the fact that we become habituated to wealth: Layard calls this "the hedonic treadmill". They blame the longer hours we work and our deteriorating relationships. But there is something I think they have missed: that wealth itself can become a source of deprivation.Having money enhances your freedom. You can travel further and you can do more when you get there. But other people's money restricts your freedom. Where you once felt free, now you find fences. In fact, you must travel further to find somewhere in which you can be free.As people become richer, and as they can extract more wealth from their property, other people become more threatening to them. We know that the fear of crime is a cause of unhappiness, but so is the sense of being seen as a potential criminal. The spikes and lights and cameras proclaim that society is not to be trusted, that we live in a world of Hobbesian relations. The story they tell becomes true, as property paranoia makes us hate each other. The harmless wanderer in the woods becomes a mortal enemy.It is hard to see how that plague of pheasants could be deemed to have caused a net increase in happiness. A group of very wealthy people, who already have an endless choice of activities, have one more wood in which to shoot. The rest of us have one less wood in which to walk. The landowners tell us that by putting down birds they have an incentive to preserve the woods - this was one of the arguments the gamekeeper used as he was throwing me off. But what good does that do us if we are not allowed to walk there?The Countryside and Rights of Way Act of 2000, which granted us the right to roam on mountains, moors, heath, downland and commons, has surely increased the sum of human happiness. But in those parts of the country that retain very little habitat of that kind (because it has been destroyed or enclosed by the land- owners), the gains we made then might already have been cancelled out by the losses, as the landlords' new opportunities for making money reduce our opportunities for leaving money behind.We need the full set of rights we were once promised, and which, in Scotland, have already been granted: access to the woods, the rivers and the coast as well as the open country. But as these places are turned into money-making monocultures, the question changes. Will we still want to visit them?