Overview
Sustainability considers how societies meet present needs while maintaining ecological and social conditions for the future. It links environmental limits with livelihoods, health, equity, and economics. A product’s impacts may shift across stages: reusable goods also require materials and washing.
Core ideas
Life-cycle assessment tracks materials and energy from extraction through disposal. A functional unit makes comparisons fair, such as impacts per hundred uses. Circular strategies include reducing demand, repair, reuse, and recycling, which also consumes energy. Ask who benefits and bears costs; indicators capture only part of reality.
Try it
Map a routine product from materials to disposal. List resource inputs and impacts, then compare alternatives serving the same function over the same period. Use estimates transparently, identify missing evidence, and consider one social effect. Suggest a practical change and a question requiring better data.
Study pathways
Study ecology, policy, economics, design, and measurement. Further reading: Khan Academy offers science and economics foundations at https://www.khanacademy.org/.