Scott Alexander (reading by Solenoid Entity / Astral Codex Ten podcast host)

but it's not really coherent deep down.

It assumes that if it got some thing, the object of desire, then it would finally be coherent and as good as the child in the mirror, and its mother would finally love it perfectly 100%.

What does it need?

Probably the thing the mother wants, traditionally the phallus.

All three of these stories come together to build Lacan's theory of desire.

At first the desire is simply for the mother.

Then the stylized father, it might not actually be the baby's father, Lacan thinks of this as a role, which he calls the paternal function, or the name of the father, which is apparently a very clever pun in French.

Tells it that it can't always have the mother.

Instead of a reward signal based on pleasing its mother, it gets a reward signal based on pleasing the abstract concept of the law, sometimes reified as dad, god, the moral law, or the set of reasonable people.

This starts with things like, don't get sexual pleasure from your mother, and don't get sexual pleasure from stroking your genitals, and don't get sexual pleasure from urination and defecation.

then moves on to more boring stuff like go to school and don't draw on the walls.

This isn't a very good reward signal because it tells the child not to do a lot of fun things and doesn't offer very much in return, but at least it avoids punishment.

But also the child constantly desires the phallus.

At some point Lacan realizes that calling it the phallus all the time is creepy and switches to the more clinical term object A.

the shadowy object of desire that would finally make it whole.

What is object A?

Lacan says that all desire is the desire of the other, which is supposed to mean that our desires are to attain the kinds of things that other relevant people desire, to be the kind of thing that other relevant people desire.

It's impossible to get object A.

If you get the thing that you were using as object A before, you won't enjoy it, and you'll just come up with a new object A. Formally, object A is the slot that desired things occupy , not the things themselves.

The pursuit of some object A is a necessary condition for having an intact psyche.