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Comment by jxramos | Hacker News Reader

is the notion of second order thinking a formal term in philosophy or logic or something? https://fs.blog/2016/04/second-order-thinking/

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I have always associated second order thinking as part of the role of a systems analyst. Systems analysis is a discipline that deals in systems and their response to changes in input or environment. The notion of second order effects are essentially the recursion of the system outputs perturbing its own inputs leading to "second order" outputs.

I have always read Chesterton's Fence is an allegory for making one self aware of these effects prior to changing a system.

I always thought of it in the sense of a Taylor expansion.

First-order thinking suggests that every system reacts linearly according to whatever the dominant factor is (the way you would basically expect). For example, increase prices and your sales will decrease.

Second order thinking suggests including the next-more-complicated effect in your model; effects that are negligible for small perturbations have to be taken into account. Increase prices and your product gets perceived as more exclusive and higher quality, and despite the valid decrease that the first-order effect predicts, sales go up.

I agree, that is a perfectly valid example. You've perturbed the system (raised prices) and there is the "expected" input and the "input that arises from the perturbation."

In mathematical logic, yes--loosely speaking, higher order logic lets us use more layers of quantifiers (https://en.wikipedia.org/wiki/Second-order_logic)

Here, the blog is referencing Mark's book on investing (link is in the blog, but direct link here: https://www.amazon.com/gp/product/0231162847/ref=as_li_qf_sp...)

The Amazon preview includes enough of the first chapter (Marks calls it "second level thinking") to get a sense of Marks's meaning

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