IB Diploma Environmental Systems & Societies HL · Environmental Ethics
Mini-Lesson
Environmental Ethics
This is the third of the three HL lenses. This mini-lesson asks not what is happening to the environment but what we ought to do: the difference between intrinsic and instrumental value, the ethical positions of anthropocentrism, biocentrism and ecocentrism, the major ethical frameworks (utilitarian, deontological, virtue), key thinkers such as Leopold and Naess, and questions of intergenerational and climate justice.
HL lens: ethics decides who counts morally — only humans? all living things? whole ecosystems? — and that choice reshapes every environmental argument.
Work through each screen, answer the questions as you go (some are wordy, some are calculations) and collect ⭐ stars. Press Start when you're ready.
Ethics · the moral circle
What environmental ethics asks
Environmental ethics studies the moral relationship between humans and the natural world. Its central move is to ask how far the "moral circle" should extend beyond humans.
Traditional ethics considered only humans morally significant. Environmental ethics asks whether animals, plants, species, ecosystems — even rocks and rivers — deserve moral consideration too, and why.
Ethics · two kinds of value
Intrinsic vs instrumental value
Intrinsic value — worth in itself, for its own sake, regardless of usefulness to anyone (e.g. a species has a right to exist).
Instrumental value — worth as a means to an end, usually human ends (e.g. a forest valued for its timber, tourism or carbon storage).
The clash between these two is the heart of most environmental disputes: is a wilderness worth protecting only if it pays, or because it matters in itself?
Quick check
Which value is it?
?A campaigner argues that a rare orchid should be protected simply because it exists and has a right to, not because it is useful to people. This appeals to the orchid’s...
Calculate
Your turn — per-capita emissions
1Country A emits 500 million tonnes of CO₂ a year and has 50 million people. Calculate its emissions per person, a key figure in climate-justice arguments.
t / person
Hint: per-capita emissions = total emissions ÷ population = 500 ÷ 50.
Ethics · three positions
Anthropocentric, biocentric and ecocentric ethics
Anthropocentric — only humans have moral status; nature matters insofar as it serves human interests.
Biocentric — all living organisms have intrinsic value and deserve moral consideration.
Ecocentric — value lies in whole systems — ecosystems, species and the biosphere — not just individuals.
These map onto the environmental value systems from Topic 1, but here they are treated as moral claims about what deserves respect.
Sort it
Sort the ethical positions
Tap a statement, then tap the ethical position it best fits.
👤 Anthropocentric
🌱 Biocentric
🌍 Ecocentric
Quick check
Naming the position
?An ethicist argues that every individual living organism — plant, insect or mammal — has intrinsic worth and deserves moral respect. This position is...
Ethics · frameworks
Three ways to decide what is right
Consequentialism / utilitarianism — an action is right if it produces the greatest overall good (least suffering) for all affected — including, some argue, animals.
Deontology (duty and rights) — some actions are right or wrong in themselves; we have duties and nature (or future people) may have rights, whatever the consequences.
Virtue ethics — asks what a good, wise person would do; values character traits such as respect, care and restraint toward nature.
Quick check
Utilitarian or deontological?
?"We must not drive this species extinct because it has a right to exist, no matter how much money the development would make." Which ethical framework is this argument using?
Ethics · the thinkers
Key ideas in environmental ethics
Aldo Leopold — the Land Ethic: "a thing is right when it tends to preserve the integrity, stability and beauty of the biotic community." Extends ethics to soils, waters, plants and animals.
Deep ecology (Arne Naess): all life has intrinsic value; humans should radically reduce their impact.
Gaia hypothesis (Lovelock): Earth behaves as a self-regulating system, inspiring holistic, ecocentric ethics.
Animal rights (Singer, Regan): sentient animals deserve moral consideration.
Ecofeminism: links the domination of nature with the domination of women.
Quick check
Whose ethic?
?"A thing is right when it tends to preserve the integrity, stability and beauty of the biotic community." This famous principle is the core of whose environmental ethic?
Ethics · justice across time
Intergenerational and climate justice
Many environmental harms fall on those with least say:
Intergenerational justice — future generations will inherit our climate and depleted resources but cannot vote today; do they have rights we must respect now?
Climate justice — the nations that emitted least often suffer most. Should historical responsibility and per-capita fairness decide who cuts emissions?
Rights of nature — some legal systems now grant rivers and forests standing, treating them as bearers of intrinsic value.
Calculate
Your turn — historical responsibility
2Of an estimated 2000 Gt of cumulative human CO₂ emissions, one bloc of nations produced 500 Gt. Calculate that bloc’s percentage share of historical emissions.
%
Hint: (500 ÷ 2000) × 100.
Calculate
Your turn — an equal carbon share
3Suppose the remaining global carbon budget is 1000 Gt and is shared equally among 8 billion people. Calculate each person’s fair share in tonnes. (1 Gt = 1 billion tonnes.)
?A low-income nation argues that wealthy nations, which emitted most of the historical CO₂, should cut emissions first and fastest. This appeals most directly to...
Match it
Match the ethics terms
Tap a statement on the left, then its matching answer on the right.
Statement
Answer
Recap
The big ideas to know
The question: environmental ethics asks how far moral consideration extends beyond humans
Value: intrinsic (worth in itself) vs instrumental (worth as a means to human ends)