Justice is about giving people what they deserve and not depriving them of what is properly theirs. Justice enjoys a commanding position among the cardinal virtues, as that which is to be sought. Applied to human life, it might seem that justice is rather a weak aim: that we certainly would not want injustice, but that other things seem necessary for a flourishing human community, such as kindness and love. That is true, but justice is a necessary backstop, and one at which we are failing, when we think about how climate change is already depriving people – indeed some of the poorest people – of land and homes.

Love holds the most exalted place in the Christian account of the virtues. In this chapter we propose that our actions are most of all determined by what we love. If we want to find the motivation to make changes to how we live, in response to climate change, we can do that best by thinking through what it is that we love, and what that might require of us. We think about how love often involves some sort of restraint or letting go (as in marriage, where we ‘forsake all other’), not out of any cold disdain, but on account of the warmth that characterises our attitude to what we love most.

Leadership on climate action is about demonstrating change in reality, not about having a senior position or being ‘in charge’. We are all involved in leadership. At work, at school, in retirement or in our leisure activities, we can demonstrate leadership by questioning default decisions and demonstrating our enthusiasm for alternatives compatible with zero emissions. Leadership could involve the four actions of Chapter 9, or speaking out among our work and community groups, or writing letters, or asking difficult questions at school. We can all show leadership, like that demonstrated by the two women who created the ‘flight-free’ movement in Sweden, and our leadership is urgently needed.

Action at scale on climate change is urgent. It is unavoidable that such action must for a period of some decades include restraint, because we do not have time to construct enough emissions-free substitutes for all today’s emitting activities. Leaders in politics and businesses cannot promote restraint without losing their jobs, so leadership must come from us, individually and collectively, making decisions to live differently. We can all act, at home and at work or in other teams. We can prioritise our most emitting activities, make changes where possible and, where it is for now beyond our reach, we can promote change through raising awareness of what matters and what help we need. These choices and actions are virtuous. Not ‘virtuous’ in the sense we parodied in the opening, of something admirable but prim and outdated, but a joyful, life-enhancing virtue that expresses the best of what we hope to be. The virtue of restraint in climate action is an act of leadership, an expression of faith and charity, and above all, an act of love.

It would be ‘convenient’ to have a climate solution, where technological innovations fix the problem without any change to current institutions, structures, and lifestyles. However, even though we have some interesting options at lab scale, innovation must be scaled up to make a difference, and it is impossible between now and 2050 for the ‘convenient’ solution to be built at the necessary scale. In addition, there can be no physically meaningful offsets because trees take too long to grow and there are no realistic emissions-negating technologies. This book’s journey to zero emissions reduces technological risk to a minimum by assuming that only technologies that already exist at scale can help, and that they will be deployed only at rates comparable with recent history. This is not ‘convenient’ in that it involves some societal change and therefore we must find the courage to act. However, we can still have a high quality of life, and expand many of the activities we most value.

In this chapter, we consider hope as the supremely political virtue, which is to say one that helps us to venture great things in the business of building a shared life. We also consider questions of scale, and the idea that we should be happy to ‘start small’ and attend, first of all, and even mainly, to the challenges and opportunities that lie closest to hand, in our homes, localities and places of work.

The proponents of the ‘convenient solution’ discussed in Chapter 3 see the cost of climate action as one of government investment in new infrastructure. However, as there is not time for this to scale sufficiently, we must think differently about cost. Voluntarily restraining ourselves from emitting activities may save us money, but in most cases at present, purchasing equipment compatible with zero emissions costs more than the emitting alternative. Eventually, governments will legislate to ban emissions, by which time we will only compare the costs of different emissions-free alternatives. On the journey to that point, governments can aim to help us change by subsidising zero-emissions projects or taxing emitting activities. Carbon pricing has proved to be politically impossible, due to competition in trade and the high costs it would place on householders. Instead, we can all re-think the timescale of our purchasing decisions and recognise that paying for the higher costs of emissions-free options today is in reality an investment in the future, like a pension or savings account, aiming to avoid the far worse costs of a global war over food.

Making a safe climate for the generations that follow us requires that we reduce our emissions to zero, at least at a steady rate, and by 2050. We can take five steps to deliver this change: understand our emissions; anticipate the moments when we take important decisions about big purchases; gather good information about the way we cause emissions in daily life; reflect on how our emissions trade off with other priorities; and re-think the main priorities and goals of our life. Living with zero emissions does not require misery, but requires restraint that can be life-enhancing, and the seed for new creativity and fulfilment.

The real threat of climate change is not about temperature, sea levels, wind or fire. It is about food. Due to global warming, the world’s total food supply will reduce to be less than total demand. This will eventually lead to a world war over food and there is a serious possibility that this could occur in this century. By 2010, we were halfway to accumulating in the atmosphere half the greenhouse gas emissions that are likely to tip us into a food war. If global annual emissions continue to increase at current rates, the atmosphere will be ‘full’ by around 2045, and starvation and war will follow. To date, our response has involved more talking than serious action, and while we have begun to make some good changes, they are at far smaller scale than required. However, we can choose to live well and soon with zero emissions, and we can prosper while we do so. This book is a hopeful one, but our hope is based on the reality of what is possible in the time available, not on dreaming that inaction now will lead to an easier option later.

For three decades, politicians have promised that new technologies will solve climate change, but they haven’t emerged at meaningful scale. So, instead we must act with technologies we already have, which will involve some restraint. However, knowing this fact does not of itself motivate change. Instead, we present a new framing of our response to climate change as an expression of our values. The restraint, perhaps lasting for two or three decades, that is required to deal with climate change is not only a sacrifice. Embracing it can also help us to find a different good life, as responsible and joyful custodians of creation. The seven virtues inspire us to lift up our heads, be honest about the options and motivate our action, and encourage us to find a safe climate, in good faith.

With this chapter we move from the ‘cardinal’ virtues of courage, prudence, temperance and justice to the ‘theological’ virtues of faith, hope and love. In particular, we ask what faith – belief in God, and in the wider Christian creed – means for what we have already considered. We see that, far from encouraging us to disregard justice and responsibility in this life for the sake of the next, it teaches us to see the world as God’s creation and other human beings as bearing God’s image, spurring us to action with all the more energy.

If we are realistic about deployment rates, we can anticipate that by 2050, we will be able to access about half the energy we would like, all of which will be emissions-free electricity. We will have very little carbon storage and cannot draw on any more biomass. This means that delivering a safe climate requires electrifying everything, halving our demand for energy and phasing out the seven non-energy activities that lead to emissions: deforestation, fugitive emissions, sheep and cows, most fertilisers, aeroplane contrails, and conventional cement and rice. Eventually these limits will be imposed on us as constraints through health and safety regulation, but for now they require voluntary restraint that we must embrace by choice if we are concerned about climate safety. However, we can live great lives within this reduced budget.

Seductive messaging about ‘convenient’ technological solutions have prevented us recognising and acting on the need for restraint as a core component of climate action, yet restraint has in the past led to faster change than technological innovation. The actions that allow us to deliver a safe climate are specified in the chapter and are highly specific. At home, we should aim to switch from gas boilers to electric heat pumps, from petrol to electric cars, to phase out our use of fossil aeroplanes and certain key foods, and we can also reduce our total requirement for energy. In teams, at work or in other contexts, we can pursue the same goals, while also aiming to reduce the construction of new large objects (buildings, vehicles, infrastructure or large equipment) and to support suppliers and customers on the same journey. As lobbyists, individually or in groups, we can influence politicians and business leaders to make it easier for us to follow the key actions that lead to zero emissions.