Kinda being slightly nitpicky here aren’t we?
https://doi.org/10.1093/oxfordhb/9780199286140.013.0029
I can use my UT library access to get the full article if you like.
Abstract
Slaves are ubiquitous, yet nearly invisible: central to the functioning of the polis, but ‘outsiders’ to it as well. In this sense, there is something else that they symbolize: the relationship between the polis and other peoples and races. This relationship is often conceived in terms of actual or potential hostility. This article deals with how the Greeks saw foreigners, and, in particular, the nature of their negative views of non-Greeks. It shows that the Greeks might not have known colour prejudice, a defining feature of modern racism, but were no less racist for that. The highly institutionalized character taken on by travel in the Greek world may be explained in part by this suspicion of foreigners and foreign lands. The article defines racism as an attitude towards individuals and groups of peoples that posits a direct and linear connection between physical and mental qualities.