Q.Sustainable development is that development which satisfies the need of:

Intergenerational Equity

The Everyday Intuition

Imagine your family has a single mango tree in the backyard. This year, it gives 100 mangoes. You can eat all 100 today — feast! — but then there are no seeds to plant, no tree for next year, and nothing for your younger sibling or your own future self. Or you can eat 80, save 20 seeds, plant them, and next year have two trees. The choice between "all for me, right now" and "enough for me, and enough for those who come after" is the heart of intergenerational equity.

You already live this idea. When your parents save money for your education instead of spending it all on a vacation, they are practising intergenerational equity. When a village protects its groundwater instead of pumping it dry, that is the same principle at a larger scale.

The Precise Meaning

Intergenerational equity is the principle that the present generation should manage resources — natural, economic, and social — in a way that does not compromise the ability of future generations to meet their own needs.

In economics, this concept is central to sustainable development. The most famous definition comes from the Brundtland Report (1987): development that "meets the needs of the present without compromising the ability of future generations to meet their own needs."

Three key ideas anchor it:

1. Fairness across time — not just fairness among people alive today, but fairness between those alive now and those not yet born.
2. Stock of capital — we inherit a stock of capital (natural resources, infrastructure, knowledge, institutions). We can use some of it, but we must leave behind at least as much total capital for the next generation.
3. Substitutability — can we replace a depleted natural resource with human-made capital? If yes, we might be able to consume more today and still be fair. If not (e.g., a extinct species, a collapsed ecosystem), then we must preserve it.

Why It Matters

Intergenerational equity is not a warm sentiment — it is a hard economic constraint. Here is why it matters for India and for any economy:

Non-renewable resources — coal, oil, minerals. If we burn all the coal today, future generations have none. They may have solar panels, but they also inherit the climate damage. The question is: are we investing enough of the proceeds from coal into things that will benefit them (roads, schools, research) to compensate for the coal we took?

Renewable resources — forests, fisheries, groundwater. These can be used forever if the rate of use does not exceed the rate of regeneration. Overfish a lake and it collapses; the next generation gets nothing. The economic rule is simple: harvest at the maximum sustainable yield, not the maximum short-term profit.

Pollution and climate change — carbon dioxide stays in the atmosphere for centuries. The costs of climate change (floods, heatwaves, lost farm output) will fall mostly on people born after 2050. The benefits of cheap fossil-fuel energy go mostly to people alive today. Intergenerational equity demands that we price carbon today so that future generations are not left with a ruined climate.

Public debt — when a government borrows heavily to fund today's consumption (not investment), it passes the repayment burden to future taxpayers. That is an intergenerational transfer in the opposite direction: the present generation consumes, the next generation pays.

The Diagram (Describe in Words)

Picture a simple graph. The horizontal axis is Time (today on the left, far future on the right). The vertical axis is Well-being (or consumption per person).

• Unsustainable path: a high, steep curve that rises sharply for the first few decades, then plunges steeply as resources run out and pollution accumulates. The present generation enjoys high well-being; future generations suffer.
• Sustainable path: a lower, flatter curve that rises steadily and stays high for centuries. The present generation has slightly less, but the line never crashes.

The gap between the two curves at any future date is the cost of ignoring intergenerational equity.

The Formula (Where It Exists) …