That's a much wider definition of externality then I was taught when I studied economics. To quote wikipedia: "In economics, an externality is the cost or benef

That's a much wider definition of externality then I was taught when I studied economics. To quote wikipedia: "In economics, an externality is the cost or benefit that affects a party who did not choose to incur that cost or benefit" So, it's not just any state of the world, but in particular that my actions cause cost/benefits to other parties.