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Economic models you can actually see move. Every curve is computed and every shift is verified. Built for students who want intuition, not just diagrams.

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Educational purposes only, not financial advice. Graphl teaches which economic framework applies and how its mechanism works; it does not solve assessment problems for you.

  1. Library
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  3. Externalities & Pigouvian Taxes
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  5. Scenario

Micro Foundations · intro

A carbon tax is introduced

What moves on the Externalities & Pigouvian Taxes diagram

  • S = MPCshifts left (small)

A Pigouvian taxPigouvian taxA tax set equal to the external harm of an activity, forcing the market to price the damage it causes. equal to marginal external cost aligns private costs with social costs, fixing the quantity.

Watch it animateQuiz yourself on Externalities & Pigouvian Taxes

Step by step

  1. 1

    The market overproduces: it ignores the red MSC gap.

  2. 2

    A tax equal to the external harm makes producers PAY the social cost, private supply and MSC merge into one line.

  3. 3

    The gap closes: the market now lands on the social optimum by itself. The externalityexternalityA cost or benefit that lands on someone outside the transaction, pollution's harm, vaccination's protection. is priced in.

Where this shows up

Examiners ask this as: carbon tax, pigouvian internalize, pollution priced.

Other scenarios on Externalities & Pigouvian Taxes

The pollution turns out worse →Demand boom for a polluting good →Cleaner technology shrinks the external cost →A dirtier process widens the external cost →Weak demand accidentally cuts the pollution →An industrial boom magnifies the market failure →