the.com/school of thought

means A group of people who share a common set of opinions, theories, or approaches within a particular field.

from Built from 'school' in its old sense of a body of followers gathered around a teacher or doctrine — the same sense behind phrases like 'the Stoic school' — rather than the building you sat in as a kid. That 'school' traces back through Latin schola to Greek scholē, which originally meant leisure or free time, the kind of unhurried time that let people sit around and argue philosophy. 'Thought' is just plain Old English, from a root meaning to think or consider. So a 'school of thought' is literally a cluster of thinkers who, in their leisure, settled on the same conclusions.