"Diminishing Returns" is a concept, or more precisely, an empirical finding that shows up in a variety of places in microeconomics. We first encountered it in the module on utility, and then again in this module on production and costs.

• What do economists mean by "diminishing returns" to an input?
• What causes diminishing returns?
• Have you ever observed this principle at work in a job you've had?
• Describe how you've experienced this concept in the real world.