Think of some environmentally unfriendly choices – taking the car instead of public transport or driving an SUV, just binning something recyclable, using lots of plastic bags, buying an enormous television, washing clothes in hot water, replacing something when you could make do with last year's model, heating rooms you don't use or leaving the heating high when you could put on another layer of clothing, flying for holidays, wasting food and water, eating a lot of beef, installing a patio heater, maybe even, as some have said lately, owning a dog.Footnote ¹ Think about your own choices, instances in which you take an action which enlarges your carbon footprint when you might have done otherwise without much trouble. Is there consolation in the thought that it makes no difference what you do?

If you didn't drive an SUV, maybe someone else would. The Americans are putting more and more cars on the road, so what's one more drop in that metallic ocean? So you throw away a recyclable bottle after lunch – it doesn't matter. Doesn't it all go in the landfill anyway? Have you seen how many plastic bags other people use – your one or two won't make a difference. What difference could your widescreen make when countries like China are producing more coal-burning power plants? Leave the heating on – it's your bill after all – and what's a few hours of wasted heat anyway, given the many millions of people who heat their homes every night? Why shouldn't you fly? The plane was going there anyway, and what difference can your comparatively little weight make? So what if you throw away food? Supermarkets throw away tons of food each day. Your tiny contribution can make no difference at all.

These are the thoughts which turn up in the heads of real people when they make everyday choices. The moral case for the claim that various countries ought to take strong action on climate change is fairly easy to see. What's much harder to spot is the moral demand for individual action, for making green choices in the course of an ordinary human life. One thing which gets in the way is the thought that nothing an individual does can possibly matter. So why bother going green? This is the environmental version of the problem of causal inefficacy. It has other manifestations too, and we'll consider some of them.

I wonder whether consequentialist reflection can somehow bring the moral demand for individual action into clear view. I want to consider, as a live possibility, the following unlikely position: one might be a consequentialist, know perfectly well that recycling today's newspaper can make no difference at all to tomorrow's climate, but still hold that there is a moral demand, having to do with consequences, for taking the paper to the recycling bin. The view might not fly, but it is worth pursuing for a reason I'll come to in a moment. First let us consider the moral case for action on the part of countries and then pin down smaller questions about individual choices in ordinary lives.

1. The Problem of Causal Inefficacy

There are plenty of arguments for large-scale action on climate change. Perhaps the most straightforward one issues in the conclusion that particular states have a moral obligation to do something serious about climate change because of their history of industrialization. Coupling facts about emissions with further thoughts about moral responsibility can make the obligation stand out clearly.Footnote ² The argument can be up and running very quickly.

Burning fossil fuels thickens the blanket of greenhouse gasses which swaddles our world and warms it up.Footnote ³ The likely effects of this increase in temperature are various and subject to different levels of certainty. There is evidence for a future characterized by hotter days and nights, rising sea levels, dwindling water supplies, altered patterns of disease, conflict over shifting resources, more dramatic weather, longer droughts, shorter growing seasons, and on and on. It seems likely that human beings are suffering and will suffer as a result of these changes – to say nothing of the suffering of our fellow creatures who will also struggle to adapt.

The pain ahead is owed to the fact that our planet's carbon sinks cannot absorb all of our emissions, and the result is dangerous anthropogenic climate change. Compared to the poor nations of the world, the richer, more developed, industrialised countries have used up the bulk of the sinks and therefore have caused more of the suffering which is underway and on the cards. A few thoughts about fairness or justice or responsibility or the importance of doing something about unnecessary suffering, coupled with these facts, issues in the conclusion that developed countries have a moral obligation to reduce emissions and help with adaptation.

Part of what makes this conclusion easy to see is the obvious causal connection between large-scale industrial activity and suffering. It's obvious in broad outline anyway.Footnote ⁴ The industrialized world has dumped a lot of greenhouse gasses into the atmosphere. Over the last 150 years, as human beings have really gotten on with industrialization, carbon dioxide concentrations have risen from 280 to about 390 parts per million – one source tells me 391.76 ppm for February 2011.Footnote ⁵ We add about one or two more ppm each year, about 1,000 tons each second.

Greenhouse gasses are changing our climate. The changes result in suffering. It is right to say that the developed world ought to go green because doing so matters – mitigation or at least adaptation will have good consequences, will make a difference to human lives. What is much harder to see, though, is the analogous conclusion when it comes to individual choices and individual lives.

One might assume that there is a fairly tight connection between thoughts about future suffering and a moral obligation to adopt a thoroughly green lifestyle. If there is a connection between greenhouse gas emissions and human suffering, then doesn't it follow that an individual ought to do all she can to reduce her carbon footprint? Isn't avoiding a hand in the suffering ahead a good personal reason for going green? The trouble is that there is a large gap between the global premises and the local conclusion.

Given the enormity and complexity of the planet's climate system, it's hard to see how a single green choice, even a whole green life, could make the slightest difference to the suffering ahead. What's my 5 tons or so of greenhouse gas emissions per year compared to 1,000 tons per second? Sort the recycling into neat piles, insulate your house, choose local produce, travel only by bicycle and on and on – in short, make a determined effort to reduce your greenhouse gas emissions to the merest whisper – and none of it can possibly make the slightest real difference to our world. An individual's teeny effects cannot matter a jot. You can be certain that the sea level will be where it will be in 2050 whether you buy the bulbs or not.

It might be true that the governments of the developed world have a moral obligation to reduce emissions. It might also be true that the world would have more happiness in it, more preferences would be satisfied, if everyone lived closer to the Earth. Given the causal inefficacy of the individual in the face of climate change, it doesn't matter that a particular person lives a life of grotesque consumption. If an individual's effects do not make a difference, doing something about climate change can't be a reason for going green. Headlines to the contrary, you can't save the planet.

There is a little disaster in this line of thought. It is hard to find a way around this disaster if you put some store in the notion that the rightness or wrongness of actions has to do with consequences. In the following paragraphs, I'll lean on this notion and see how sturdy it is. In the end, we'll have to shore it up a little, but I think it turns out that individual green actions can be motivated by reflection on consequences. I admit that it is a fractionally round-about line of thought, but maybe it is better than an alternative or two.

Why should we lean on the notion? Why not, say, just go Kantian or cultivate personal virtue in this connection? The short answer is that thoughts about consequences have a certain hold on us when it comes to doing something about environmental degradation. We see the results of climate change – not just on the news but in our gardens – and a common reaction is the desire to do something about it, to take action. Contrary to a recent dispatch from the Vatican, probably most people are not ready to see harming the environment as a kind of vice or anyway as a lack of virtue.Footnote ⁶ The many environmentally friendly actions one might undertake are seen as precisely that, actions, and we undertake them principally for the consequences which result from them. We think we are doing good, not being good, when we take certain steps to save energy. We have a better world in view, not a better character.

The little disaster is the possibility that we cannot really do any good at all. If you already have Kantian leanings or think of your green activities as virtuous, then maybe you're not the person I am to convince. The person I hope to persuade is one who sometimes leans on that thought about consequences, who wonders how her consequences could possibly make a relevant difference – a person on the verge of thinking that it makes no difference what she does.

The problem of causal inefficacy gets a hearing against the backdrop of utilitarian arguments for vegetarianism and further reflection on voting, and some other questions too. The plan is to make a start by using these discussions to try to get a handle on climate change and causal inefficacy. Maybe we can leapfrog to an answer to our version of the problem by making use of the good thoughts of those who have already done some work in this neighbourhood. Consider vegetarianism first.

2. Threshold Chickens

Singer has argued that there is a strong and obvious connection between the obligation to become a vegetarian and utilitarianism. He originally maintained that ‘because becoming a vegetarian reduces the overall demand for animal flesh, an individual could assume that it lowered the profitability of the animal industry, and thus reduced the number of animals factory farmers would breed’. Footnote ⁷ The choice not to eat animals, it might be thought, saves animals from suffering. As several critics point out, though, the loss of just one meat-eater from the millions and millions of consumers in a market makes a difference too tiny to be a noticeable difference to factory farmers.Footnote ⁸ It's not possible to say that an individual's choice to become a vegetarian has an effect on the number of animals killed. Just as the climate will do what it does whether or not an individual goes green, the size and complexity of the factory farming industry is such that a single individual's choices cannot possibly register.

One set of responses to this has to do with thresholds. It might be true that just one vegetarian does not make a substantial difference, but a large number of vegetarians must make a difference. Maybe for every 10,000 vegetarians one fewer 100,000-bird factory farm is needed to supply the market. If enough people become vegetarians, the demand for meat drops below a certain threshold, producers take note, and a farm closes.

This can all be interpreted in a number of ways. You might think that whether you choose to be a vegetarian or not makes no difference at all to the market, unless you happen to be the lucky person who pushes the number of chickens demanded by the market down under the critical threshold. There's a chance it might be you, and since the stakes are so very high maybe that chance is enough to nudge you away from meat. Or you could understand your tiny role in boosting the numbers of vegetarians as contributory in some sense – as maybe not pushing the numbers past a threshold but nevertheless having a not entirely inconsequential part to play in swelling the ranks and closing one big factory farm. Maybe this little hand in ending a large wrong conveys enough utility to make the choice to go veggie the right one.

Let us take the main arc of this thinking about thresholds and try to adapt it to the case of climate change. If enough of us become vegetarians, then the demand for meat has to decrease, the market has to notice, and animals have to be saved from a horrible life on a factory farm. Can we say the same sorts of things about going green? Can we really see the same sorts of connections? Maybe there is a parallel thought with respect to climate change, but I suspect that it's too murky to help us if we are after a consequentialist motivation for environmentally responsible action. Try to get a grip on the relevant antecedent and consequent.

The antecedent – which we might render as ‘If enough of us go green …’ – is hazy, partly because we do not yet have a clear take on what it means to go green. Going green is a much more amorphous proposition than going vegetarian. Certainly there are different sorts of vegetarians, and no doubt it's a complex thing, but probably there are fewer wrinkles in going vegetarian than there are in going green. If you are a vegetarian, at bottom that means that you don't eat meat. Maybe we can argue about the finer points of that statement, but certain things are just right out. But what is it, at bottom, to be green?

Probably there are things to be said about the fact that we have not yet settled on what ‘going green’ actually means. It's a new thought for most of us. We do not yet have a good grip on how to reduce our impact on the Earth. Consider a few very common questions. Should I throw away my old bulbs (and thus waste the energy which went in to making them) or wait until they burn out before replacing them with the environmentally friendly ones? Should I buy local produce (and save on food miles) or buy Fair Trade from abroad (and help the poor farmers in South America)? Should I avoid flying altogether or offset my emissions with a clear conscience? Should we risk nuclear power in an effort to avoid greenhouse gas emissions? I have heard someone wonder if it's better to keep the air conditioning on in a car with the windows up (and thus reduce drag) or roll down the windows and turn off the air conditioning (and lower demand on fuel). These questions range from hard to trifling, but the point is that they are many, and some answers are not obvious.

Consider the consequent. How do we fill it in? ‘If enough of us go green (however we spell that out) then’ … what? An easy thought to have is that the concentrations of greenhouse gases in our atmosphere will level off or drop, but it's hard to spell out how this works in enough detail to keep a solid response to the problem of causal inefficacy in view. We know a lot about how the climate works, but there's a lot we do not know, too. I am by no means suggesting that there is uncertainty with regard to climate change where it counts. We know that human beings are causing the change, and we know a lot about the nature of that change. We do not know much about regional variations and local impacts, and we do not know much about the timing of the changes ahead. There is a lot we do not know about feedbacks and thresholds. These gaps in our knowledge add uncertainty to our reflection about our effects.

It's not just our ignorance. Even concerning some aspects of the problem where we have a good understanding of what is going on, the complexity itself is overwhelming. It can make the relevance of the threshold response fade when it comes to climate change. Don't worry about green causes or the anticipated effects, but consider what's in between. One can, nearly, think about market forces and farmers and producers and buyers and come to the conclusion that enough of a change here will cause a change there. Maybe that conclusion can lead to vegetarianism.

Can we do the same sort of thing with, say, our greenhouse gas emissions and the global effects of climate change? Bear in mind, as you think about the answer to that question, that it might take a supercomputer a quadrillion different operations and more than a month to manipulate a climate model. There are feedbacks associated with ice and snow, animal life, clouds, wind, rain and on and on. Further, our effects are smeared out not just in space, but in time as well. Our emissions join together with past and future emissions and have further effects which might well be both spatially and temporally distant from us. It is hard to see a straight line from leaving my DVD-player on standby to melting ice caps.Footnote ⁹

All of this is not to say that a person cannot see her role in all of this and come to the conclusion that, if enough people take serious action on climate change, we might, together, have good effects. I have that conclusion in my head from time to time, but I think it comes from something other than reflection on thresholds and causal chains and emissions. The difficulty I want to highlight lies in turning thoughts about thresholds into a consequentialist reason for green choices. In short, the weaker our grip on our place in the causal network the more difficult it is for causal thresholds to serve as a motivating reason for action. In the case of climate change, our conception of how our actions fit into the causal network is feeble to say the least. Maybe my effects are so small, and the world so huge, that I just can't talk myself into seeing what I do as playing any role at all in crossing any sort of threshold. Although a proto-vegetarian stands a chance of getting certain thresholds in view, seeing analogous thresholds in the climate change case might well be beyond us. Let us look elsewhere for help.

3. The Principle of Divisibility

Glover usefully distinguishes between two sorts of thresholds: absolute and discrimination thresholds.Footnote ¹⁰ An absolute threshold exists where there is a sharp boundary between two different outcomes. As he says the clearest example is voting. It's all or nothing – either one candidate gets enough votes and is elected or not. In a sense there's no point in your voting unless the race is so close that a single vote will swing it one way or another. If you have consequentialist grounds for voting, your reasons can't have much to do with the election's outcome.

Where there is a discrimination threshold, however, an individual's single act can only nudge the situation fractionally in the direction of some outcome. Effects are widely spread out, and an individual's contribution might go unnoticed. There's no easily visible threshold to cross. Instead, ‘reality is a gentle slope, and the threshold is defined by the distance apart on the slope two points have to be in order to be seen as separate by us.’Footnote ¹¹ To borrow Glover's example, if there is a power shortage and I keep my heating on even though we're asked to conserve energy, the power cut we endure will be a fraction of a second longer than it might have been had I done my civic duty. No one will notice my misdemeanour, but things will get worse, will slide down the slope, if more people do as I do. Although Glover does not address the subject, probably we can think of climate change in terms of discrimination thresholds. It's not as though anyone can say that one more office photocopier left on at the weekend will hurl us over the brink.

In the case of absolute thresholds, we can see clear outcomes and apportion praise and blame accordingly, but with discrimination cases, we sometimes think it makes no difference what we do. However, Glover argues, one really is responsible for the fraction of the harm done in discrimination threshold cases. According to his Principle of Divisibility: ‘in cases where harm is a matter of degree, sub-threshold actions are wrong to the extent that they cause harm, and where a hundred acts like mine are necessary to cause a detectable difference I have caused 1/100 of that detectable harm.’Footnote ¹²

Glover's example, having to do with bandits and beans, draws out the absurdity in the denial of the principle – in thinking that it makes no difference what you do in discrimination cases. Suppose 100 villagers sit down to a lunch of 100 bowls containing 100 beans each. 100 hungry bandits descend on the village and take one bowl each, at gunpoint, leaving the villagers hungry. They each do a discernable amount of harm. There's an absolute line that each bandit crosses, and the result is hungry villagers.

But suppose each bandit takes just one bean from each bowl. If you reject the principle of divisibility, you might conclude that although the bandits still eat all the beans, they nevertheless do no wrong, as each one does an indiscernible bit of damage. The villagers will probably disagree with you. The point is that indiscernible damage is still damage, and one really is responsible for one's share of the wrong.

Does this help someone genuinely concerned about the morality of individual choices and climate change? We are now talking about something other than 1/100 of some detectable harm.

There are nearly 7 billion people on the planet. Together we emit 28.4 gigatons of CO2 each year.Footnote ¹³ A gigaton is one billion tons. By comparison, I am responsible for about 4 tons of CO2 each year. Am I to see myself as responsible for 4/28.4 * 1,000,000,000 or 0.000000000141% of the harm done to our planet this year? Should I try to do better and aim for 4/28,399,999,999?

I can go along with the Principle of Divisibility and admit that I have a share in a slow-motion disaster. Even so, in this case at least, the harm I do is so impossibly teeny that it can't figure into a real motivation for green action. I can't really see it. We'll have to look for help elsewhere.

4. Side effects and Spirals

There are other sorts of replies to the problem of causal inefficacy. Vegetarians sometimes admit that the consequences of going veggie might be difficult to see when it comes to animal welfare, but there's plenty of personal utility to be had in the health benefits of becoming a vegetarian. Maybe there's enough utility in improved health to make vegetarianism a moral requirement. I suppose one might argue, in a similar spirit, that taking certain green steps will save one a bit of cash in fuel bills. Maybe you'll avoid a plane crash if you cut back on flying.

There is another, maybe more familiar thought that one's effects can spiral out into the causal network – that maybe my efforts will be seen by others who will, in turn, follow me and also be example to yet more people. Certainly some carnivores change their diets after talking things through with a committed vegetarian. Maybe others will recycle if I they see me doing it.

If it's not clear that even one animal avoids suffering as a result of an individual's dietary choices, it is possible that other, good effects can result. Maybe the same is true of individual action on climate change. Perhaps turning off the heating won't matter when it comes to the climate itself, but I'll save a bit of cash. I might even have more effects on others which, all told, add up to something with a serious consequence on the climate. Given the size of our world's planetary systems, it would have to be one impressive spiral, but maybe my going green is just the start of a huge avalanche of change. Who knows?

It all might be true, but it feels like looking away from where the moral weight ought to fall. Such thoughts are ‘one thought too many’, as Williams puts it.Footnote ¹⁴ Probably a vegetarian wants the rightness of her behaviour to have something to do with animal welfare, not her own welfare. Someone who turns down the thermostat wants that act to be the moral crux of things, not the money saved or the possibility that, somehow, she might be the next Al Gore. Maybe we'll be forced out of this thought, but it's the main effects, not the side-effects that should be at the very centre of our thinking, shouldn't it?

There are familiar responses having to do with utilitarianism and correcting our moral intuitions, not pandering to them. You can take this point, maybe get a feel for where the argument is headed when it comes to climate change, and keep looking for something else which lines up with your hope that the rightness or wrongness of your actions has to do with something other than side-effects and spirals. That's what we'll do.

5. Larger lives

As we saw a moment ago, there is a sense in which a single vote is causally impotent. The point arises also in some considerations of democracy and free riding.Footnote ¹⁵ In an electorate of sufficient size, I might anticipate a close race, but probably I cannot really think that it's going to be so close that my vote will actually break a tie. Perhaps every vote counts in the sometimes optimistic sense that every vote really is counted, but it makes no difference whether or not any particular individual votes.

If you look away from responses to this problem which sound like the ones we've already considered – and don't be too distracted by debates about the merits of act and rule utilitarianism either – what you find can strike a chord. There is the claim that one has a moral obligation to vote, and this is rooted sometimes in talk of duties which simply fall out of citizenship. Maybe other moral demands are mentioned, perhaps honouring the memories of those who fought for suffrage. It can be a complicated set of motivations.

Even more suggestive, given the consequentialist thought we want to lean on, is the claim that voting is best understood as something much more than marking a page or pulling a lever. It can be an expression of all sorts of thoughts and principles which together result in the vote itself, as well as all sorts of other actions and further thoughts, which together are part of the meaning of a life. Voting is something people do because of the people they are, the lives they live, maybe the hopes they have. You might have heard expressions of this sort of thing in the run up to the 2008 US presidential election. Votes are not just momentary acts, but consistent parts of larger lives.

This aspect of the response made by certain voters is echoed in the claims of at least some vegetarians. Singer puts it like this:

The thought is that becoming a vegetarian is something larger than simply not eating meat. Choosing to be a vegetarian creates a psychological tie not just to a certain sort of action, but to a kind of life. Maybe most importantly, thinking of vegetarianism in this sort of way makes it clear that avoiding meat is a choice consistent with various beliefs and principles. Voting can be an expression of a similar sort of consistency. Being a vegetarian is not just a momentary choice of what one might have for lunch, just as a vote is not just a mark on a page. Both actions might be thought of as consistent parts of larger agenda, hopes, practices and plans – parts of whole lives if you like.

There is something admittedly wishy-washy about all of this, and certainly no arguments have been offered to force this kind of holistic view of vegetarianism or voting on us. What I find suggestive here, though, is the notion of consistency.Footnote ¹⁷ I might have to vote or chose to eat in one way rather than another because doing so is consistent with the principles I hold or perhaps consistent with my thinking on nearby problems. If so, then I might have consequentialist grounds for acting, even though my actions probably have no relevant consequences. If that way of putting it jars too much, you can think of the grounds as nearly-consequentialist or partly-consequentialist. Let us follow this thought as it applies to climate change.

6. Consistency

Consistency isat the centre of a great deal of our thinking about morality. If someone in such and such a situation deserves a certain sort of treatment, then the demand for consistency tells us that others in that situation deserve the same treatment too. If times are tough for me, and I think you ought to share what you've got, then I know I ought to share out what I have when things are going well for me. You can be an atheist and still think that you should do unto others what you would have them to unto you. The demand for consistency leads a utilitarian to think that everyone's pleasures and pains ought to figure into our calculations, not just her own. It's part of a Kantian's reason for universalizing maxims. It makes moral debates something more than expressions of emotion. Maybe consistency is part of the reason a voter votes and a vegetarian avoids meat. Such actions are consistent expressions of a collection of attitudes and beliefs – they are consistent and coherent parts of lived human lives.

Consistency can provide a utilitarian with a reason for favouring individually green choices too. It's a round-about reason, but it's not just one thought too many, and it side-steps the problems we found with other responses to the problem of causal inefficacy. Here is a cartoon version of how this line of thinking might go. It takes a fairly common moral argument about the US and action on climate change and insists on consistency between that argument and reasons and actions in an individual life. Numbers make it a little more clear, but you can imagine doing without them. It depends on the global arguments one accepts, as well as the principles which govern a life, coupled with the demand for consistency in our thinking and acting. This generic version is only meant to be suggestive.

A consequentialist can, rightly, denounce the world's biggest polluters for failing to take strong action on climate change. The US, for example, with just 5% of the world's population, is responsible for around 25% of the planet's greenhouse gas emissions.Footnote ¹⁸ Recall that short argument for government action on climate change at the start of this paper. The developed world is causing the largest amount of damage. If you think causal responsibility is tied to moral responsibility for action, then probably you think that the biggest polluters have the largest moral obligation to do something about climate change. The US is doing a lot of damage to the climate, and this damage will cause human suffering. There are numerous consequentialist reasons for thinking that the US ought to change the way it uses energy, ought to minimize its carbon-footprint, ought to help the poor of the world to adapt to the changes already underway. In short, the biggest polluters have the biggest obligation to take meaningful action on climate change.

There are some principles operative in such thoughts, and if you apply them to an individual life, you might be drawn to a solution to the problem of causal inefficacy. The premises and principles operative in your thinking about the world's biggest polluters, mutatis mutandis, apply to you too. It might be that you ought to take strong action on climate change, and that you are doing wrong if you do nothing, for familiar reasons. Consistency provides the necessary linkage.

If, for example, the US is wrong to do nothing about climate change despite being responsible for the most emissions per country, then maybe consistency demands that we think of ourselves as wrong to do nothing about climate change, despite being responsible for the most emissions per capita. People who live in the US, Canada or Australia are responsible for about 20 metric tons of carbon dioxide on average each year. People in many EU countries, like Denmark, the UK and Germany, emit about 10 metric tons on average.

Residents of more than half of the countries on our planet emit less than 5 metric tons on average. Residents of more than a third of the countries on the planet are responsible for less than even a single metric ton each year. Many human beings are responsible for no measurable emissions at all. Compared to most people on the planet, the greenhouse gas emissions resulting from our individual lives in the West are massive. You might be doing 20 times as much damage to the planet as many other people in the world.

Think again about consistency. If you are a utilitarian with good consequentialist grounds for thinking that the world's biggest polluters ought to take strong action on climate change, then maybe consistency demands that the everyday choices in your life must be much more green.

Probably you ought to take serious action to reduce your carbon-footprint. You should not fly. Get a bike. Work out what resources you use and use only those which make a real difference to you. Let ‘Reduce, reuse, recycle,’ be your mantra. Turn down the thermostat right now. Unplug everything. Give money to green charities. Devote considerable time to lobbying your national government and your local representatives. Put some pressure on environmentally unfriendly corporations too. Buy the bulbs, and on and on. You even have to recycle that little coffee cup lid.

You can think all of this, perfectly consistently, right alongside the thought that it makes no difference whether or not the coffee cup lid ends up in a landfill. Your little green actions can make no real difference at all, but you still ought to undertake them. You have a moral obligation which depends on the demand of consistency in thought and action, on the reasons you have for thinking what you do about governments and what obligations they have, as well as the sort of life you hope to lead. Your reasons for this conclusion can have a lot of relevant consequences in them, consequences having to do with the Earth, large scale social change, re-powering our fossil-fuel burning world, and avoiding the suffering of human beings – even though many of those consequences have nothing to do with your particular thermostat. Your reasons can be bolstered by their consistent position in the rest of your projects, the rest of your green life. You have to do the green thing, even if doing so makes no difference at all.

7. Concluding thoughts

It might be said that there is something suspect in a line of thinking which bounces back and forth between the moral demands placed on individuals and the moral demands proper to whole governments. Plato got into trouble with that sort of thing, but I don't think the call for consistency in our thinking and acting amounts to anything as embarrassing as a shaky argument by analogy. There is the familiar thought that we are very good at spotting local, hometown wrongs but awful at working out what to do when the enormous scale of harm overwhelms us. It might somehow be true, too, that we can spot huge and obvious wrongs while missing little outrages in our own lives. Bouncing back and forth like this might end up mattering when it comes to facing up to global rights and wrongs as well as finding a way to think of ourselves in the midst of it all. It might pull us in both directions, maybe help us see both scales a little better. The bouncing back and forth might be a recommendation of this reply to the problem of causal inefficacy.

Maybe there is fast talk in this stuff about the whole of a life. I'm certainly not saying that the whole of a life has enough in the way of effects to make a difference to the planet, but what is being said is still only rough and ready. Agreed that what we have here is just the first step in what might have to be a long line of thought. It's just an argument for connecting our thoughts about the world at large to our thoughts about our individual lives. Large, global conclusions are easy to see when we look at the actions of governments, but we lose our grip when we apply those thoughts to the little specks of our lives. What's needed is a better way of understanding a whole life, and maybe reasons for thinking that a life guided by consistent moral principles is worth pursuing.

Is there something funny in the different uses of ‘responsible’ in the US case and in your case? In the former case it's true that the US is causally and morally responsible for a lot of damage, and in the latter case it's only true that an individual is responsible for high emissions per capita, for more damage than most people but still not much in itself. The real consequences are on just one side of the ledger. That might be true, but the point is not to show that an individual is really responsible for anything. I'm admitting that an individual's effects don't add up to much. The aim is to make a connection between our thinking about large and small responsibilities, between our judgements about the US's conduct and our own lives.

Is this all still consequentialism? I have doubts about this, but there really are still consequences in the arguments just scouted, even if the consequences aren't mine. I admit too that I get fairly close to virtue ethics when I talk about going green as being part of a larger life, choices made because of the person one wants to be, and maybe I am drawn to thoughts about virtues in the end. When I avoid a long-haul flight, I know it makes no difference whether or not I fly. I take the train partly because of my global judgements about the US and others, about the way I think the world ought to go, the hopes that I have for future human beings, and the sort of person I aim to be. There's plenty of reflection on consequences in those thoughts. If my life is to be consistent with all of that, I can't just hop on a plane.

I admit that I've been sloppy with the word ‘consistency’ too – I've used it in different ways. There is a kind of bedrock notion of consistency at the heart of morality, another conception at work when we talk about the consistent application of moral principles to governments and ourselves, another operative when we talk about consistency in our judging and acting. It's this last which most interests me. I'm after a conception of consistency as a demand for action based on a connection between belief, principle and behaviour – walking the walk, in other words. Montaigne says that, ‘The true mirror of our discourse is the course of our lives.’ There's a sense in which our words sometimes have to commit us to action. Our actions just have to be consistent with our thoughts. How and why this should be so is worth a great deal of reflection. I don't have a grip on it yet, but talk of consistency is as close as I can get at the moment.Footnote ¹⁹

What really matters, though, is whether or not these sorts of thoughts get us past the problem of causal inefficacy with respect to climate change. I don't think that the consistency move will work for everyone troubled by the problem. Most human beings need to pile up a lot of reasons before they start doing all that a green life demands, but I am hopeful that plenty of reasons are out there. Maybe the demand for consistency is one of them. Talk of consistency does strike me as more promising, more convincing than talk of thresholds, spirals and the like. It still leans on consequentialist thinking, but shores those thoughts up with something very solid, something at the heart of a great many good thoughts on morality.

If the argument works, it does so by thinking of environmentally friendly choices as something other than little, individual actions which might have good or bad consequences. Being green, however we settle on the meaning of it, is something like a way of life – going on in one way rather than another, as Wittgenstein put it. Choosing to live in a certain green way, a way consistent with various judgements, principles and facts, will make no difference at all to the sea level in 2050. It is, nevertheless, the right thing to do.Footnote ²⁰