Climate change policy decisions are inescapably intertwined with future generations. Even if all carbon dioxide emissions were to be stopped today, most aspects of climate change would persist for hundreds of years, thus inevitably raising questions of intergenerational justice and sustainability. -/- The chapter begins with a short overview of discount rate debate in climate economics, followed by the observation that discounting implicitly makes the assumption that natural capital is always substitutable with man-made capital. The chapter explains why non-substitutability matters (...) if we are to take intergenerational justice seriously and invest aptly in mitigation. Non-substitutability simply implies that there are some forms of capital that cannot be substituted by another, and so consumption of one cannot be compensated with additional stocks of the other. The non-substitutability of critical natural capital can be defended without empirical data about preferences or the need to view the environment as a superior good, and the argument is presented through the language of keeping options open. -/- Those alive today make decisions about what natural capital to use and what to save for future. These choices are often represented as different points in a continuum of sustainability: weak sustainability is associated with a high degree of substitutability and therefore a lot of flexibility over what capital to consume, whereas strong sustainability is more stringent on substitutability. While it may be that in economical understanding weak and strong sustainability collapse into one another, philosophically the emphasis is slightly different. The chapter discusses how normative sustainability can be supported without ignoring opportunity costs and trade-offs. (shrink)

According to the procreation asymmetry there is no moral reason to create a new and foreseeably happy person just because this person will be happy, but there is however a moral reason against creating a new and foreseeably unhappy person just because this person will be unhappy. A common way to defend this conjunction of claims is by employing a so-called existence-requirement, according to which the happiness of a given person p in a world w depends on it being possible (...) to understand p as an existing person in w. The aim of this paper is to consider whether this existence-requirement strategy is compatible with other intuitions and convictions held in normative moral theory and populations ethics. This aim will be achieved by considering whether the existence-requirement strategy is compatible with three plausible desiderata for a solution to the procreation asymmetry. Although some solutions to some potential incompatibilities are suggested, the thesis that will be argued for is that every instance of the existence-requirement strategy is incompatible with at least one of the relevant desiderata. Where the common denominating incompatibility for all instances of the existence-requirement strategy is to be found in an inability to be sufficiently action-guiding. (shrink)