What goes for seeing trees, goes the same for "treating individuals as individuals": the _process_ of getting to know someone as an individual, involves exploiting the statistical relationships between what you observe, and what you're trying to learn about. If you see someone wearing an Emacs tee-shirt, you're going to assume that they _probably_ use Emacs, and asking them about their [dot-emacs file](https://www.gnu.org/software/emacs/manual/html_node/emacs/Init-File.html) is going to seem like a better casual conversation-starter compared to the base rate of people wearing non-Emacs shirts. Not _with certainty_—maybe they just found the shirt in a thrift store and thought it looked cool—but the shirt _shifts the probabilities_ implied by your decisionmaking.
What goes for seeing trees, goes the same for "treating individuals as individuals": the _process_ of getting to know someone as an individual, involves exploiting the statistical relationships between what you observe, and what you're trying to learn about. If you see someone wearing an Emacs tee-shirt, you're going to assume that they _probably_ use Emacs, and asking them about their [dot-emacs file](https://www.gnu.org/software/emacs/manual/html_node/emacs/Init-File.html) is going to seem like a better casual conversation-starter compared to the base rate of people wearing non-Emacs shirts. Not _with certainty_—maybe they just found the shirt in a thrift store and thought it looked cool—but the shirt _shifts the probabilities_ implied by your decisionmaking.