Growth-Oriented Definition — Paul Samuelson

Paul Samuelson, one of the most influential 20th-century economists, offered a definition that tried to combine the strengths of the wealth, welfare and scarcity views while explicitly adding a time and growth dimension:

"Economics is the study of how men and society choose, with or without the use of money, to employ scarce productive resources, which could have alternative uses, to produce various commodities over time and distribute them for consumption, now and in the future, among various persons and groups in society. It analyses the costs and benefits of improving patterns of resource allocation."

What Samuelson's definition adds over Robbins:

• It explicitly brings in the time dimension — production and consumption happen "over time" and cover "now and in the future," directly connecting Economics to the idea of economic growth and development, not just a one-shot allocation decision.
• It retains the choice/scarcity core from Robbins — resources are still scarce and have alternative uses.
• It reintroduces a welfare-like concern implicitly, through its reference to analysing the "costs and benefits of improving patterns of resource allocation" — i.e., Economics is not neutral about whether an allocation is better or worse.
• It explicitly allows for a barter or non-monetary economy ("with or without the use of money"), widening the scope beyond a purely monetary science. …