Words With Blurry Edges
A series on the vocabulary of mind — five words we use to describe consciousness, traced through the long history of their shifts.
What does it mean to be sentient? Ask three researchers from different fields and you'll get three definitions with no significant overlap. Ask them again in ten years and the answers will have shifted again. This isn't confusion — it's language doing what language does on hard problems.
There's a cluster of words that orbit the idea of mind: sentience, attention, intelligence, empathy, sapience. They're used today — heavily, urgently — in debates about AI, animal cognition, moral status, and consciousness. Each carries long freight: etymological roots, centuries of competing technical definitions, folk meanings that crept in and calcified, and recent redefinitions pulled in different directions simultaneously by machine learning, cognitive science, and philosophy of mind.
This series is a diachronic pass over that vocabulary. Not a disambiguation guide — the ambiguity is the point. When a word's meaning shifts, it's usually because something in the underlying conceptual framework shifted first. Tracing the word is a way of locating the seam.
My angle is philological. I'm interested in when words changed, what was changing around them when they did, and what successive definitions reveal about the conceptual commitments of the people using them. Less "here's the right definition" and more "here's the fault line, here's when it opened, here's which side people fell on."
Why these five words specifically? Because they're all doing double or triple duty right now, in domains that don't talk to each other much, with each domain confident it's using the term correctly.
Sentience in Buddhist philosophy means something close to the capacity to suffer — it's the criterion for moral consideration, coextensive with all animate life down to the insect. Sentience in AI discourse often means something like "there is something it is like to be this system" — Nagel's formulation, the hard problem in miniature. These are not the same concept using the same word. They're different theories of what matters, wearing the same costume.
Intelligence is in some ways the wildest case. The word has had a technical definition in psychometrics since Spearman, a colloquial meaning that barely overlaps with it, and now a third life in artificial intelligence where it mostly means "can do tasks we thought only humans could do" — which is not a definition, it's a moving target.
Attention started as a phenomenological term (what it means to direct the mind toward something), became a technical construct in cognitive psychology (selective attention, attentional resources), and then, with the transformer architecture, became a specific mathematical operation that produces something that behaves a little like attention and is now almost inseparable from it in everyday usage.
Empathy is the youngest of the five — the English word is barely a century old, coined as a translation of the German Einfühlung (feeling-into), itself a term of art in aesthetics before it migrated to psychology. What it refers to has been contested since the start.
Sapience is the rarest in technical discourse but the richest etymologically — it shares a root with sapor (taste, flavor), with Homo sapiens, with the Sophia of philosophy. Its history is about a capacity to discern, to judge well, that consistently gets collapsed into intelligence and then mourned as missing.
Five words. Five series of shifts. The plan is one entry per word, long-form, following each term through its history without forcing a conclusion about what it "really" means.
The goal isn't to resolve the ambiguity. It's to get a better map of the terrain — so that when someone says "sentient AI" or "machine empathy" or "artificial general intelligence," we have some sense of which tradition they're inheriting, which they're ignoring, and what's actually at stake in their choice.
Entry one is sentience — the oldest, the most concrete in origin, and the one that has traveled the furthest from where it started.