My good friend (though we’ve by no means met) and fellow economist Jon Murphy said lately, in a touch upon co-blogger Pierre Lemieux’s current put up:
When there are two choices shifting you away out of your desired path, selecting the one which strikes you away barely slower just isn’t actually any higher.
I challenged Jon, writing:
Sure it’s. Assume on the margin.
Jon is nice at considering on the margin. I believed he would agree. However he didn’t. As an alternative he wrote:
I’m, David. My level is that each choices as offered lead me additional away from my aim. That means it’s time to get your hands on a brand new margin or do nothing.
Commenter Vivian Darkbloom got here in on my facet of the difficulty, writing:
Being on the 30 yard line just isn’t the identical as being on the ten yard line!
To which Jon responded:
Agreed. However when my aim is to be within the endzone, one play that drops me again to the 40 and one other that drops me again to the 50 are each counterproductive.
Sure, each are counterproductive, however in economics we regularly evaluate two unhealthy alternate options and select the much less unhealthy. Considering on the margin works right here too. 40 is nearer than 50.
Now, if Jon had argued that the 2 alternate options aren’t any totally different, then he would have some extent. However he made fairly clear that that’s not what he’s arguing.
Be aware: Pierre raises one other concern within the feedback, in response, and it’s a very good level for Pierre to make. Nevertheless it isn’t related to my response to Jon.