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This is maybe as good a time as any to discuss the usual alternative presentation of transducers that I find is a far gentler introduction.

A transducer is simply a function of the form `a -> List<b>`. Yes this is fully polymorphic, i.e. it holds even for transducers that only operate over just lists.

In this case `mapping` is just

This lens views a transducer through the lens of the `eduction` function as a more souped up `map`. Whereas with a normal `map` you only get to use a function `a -> b`, which means you can't change the underlying structure, with `eduction` you get to use `a -> List<b>` (again a transducer), where you "keep" any elements that are in the output list and you "discard" any elements not in the output list.

So e.g. `mapping` would be:

    (defn mapping [f] (fn [x] [(f x)]))

or in Python

    def mapping(f):
        return lambda x: [f(x)]

and `filtering` would be:

    (defn filtering [f] (fn [x] [if (f x) [x] []]))

or in Python

    def filtering(f):
        return lambda x: [x] if f(x) else []

In my opinion way clearer and easier!

For more details on the full equivalence see https://news.ycombinator.com/item?id=27778423

The current presentation of transducers has always felt like a wart in Clojure.

Having seen LLMs so many times produce coherent, sensible and valid chains of reasoning to diagnose issues and bugs in software I work on, I am at this point in absolutely no doubt that they are thinking.

Consciousness or self awareness is of course a different question, and ones whose answer seems less clear right now.

Knee jerk dismissing the evidence in front of your eyes because you find it unbelievable that we can achieve true reasoning via scaled matrix multiplication is understandable, but also betrays a lack of imagination and flexibility of thought. The world is full of bizarre wonders and this is just one more to add to the list.