Justin E. H. Smith in his Substack newsletter, Hinternet:
Psychology, as a scientific discipline in its own right, appears towards the end of the nineteenth century at roughly the moment when it is no longer possible in respectable institutions to speak of the soul. To put this another way, the science of the soul, which is all the word “psychology” means, begins only when those concerned with it declare the soul off-limits within the scope of their science. This might seem paradoxical, but in fact it is a common pattern: “biology” comes into its own, too, only when it ceases for the most part to look for that special je-ne-sais-quoi we call “life” that would somehow place living beings at a different ontological rank on some imagined “scale of being” from helium or silica, and just gets down to the business of accounting for how a certain class of carbon-based compounds do their thing. Philosophy for its part would still be able to talk about the soul in some limited contexts, but typically only as an occasion for investigating other conceptual problems or as shorthand for the gedankenexperimental fiction of a fully disembodied conscious being. Still, “Does the soul exist?” remains even today a legitimate topic of inquiry in a typical Intro to Philosophy course, though I suspect many instructors rush at the beginning of this segment to reassure their students that they personally know full well that it does not.
What you will not find anywhere in the current practice of philosophy is any serious examination of a perfectly reasonable follow-up question: “The soul of what?”
More here.