Russell begins this essay by noting the recent (modern - late 19th/20th century) transformation of education from "a small, highly skilled profession concerned with a minority of the population, to a large and important branch of the public service." Although this shows that education has become available to more people, Russell sees problems with state-run education and how these problems can limit the function of a teacher.
Russell notes that while innovative teachers of the past (Socrates, Galileo) have been persecuted for teaching non-traditional doctrine, their work survives and is therefore proof that they had the intellectual freedom to think and teach such non-traditional ideas. Russell adds that for a teacher to fulfill his/her role as a teacher, he/she must feel this sense of intellectual freedom and independence.
Russell cites examples where education is censored (Nazi Germany and the Soviet Union), nations where teachers must not question the dogma of their respective governments. This limits the teacher's intellectual freedom and he/she must therefore teach students to think only within the beliefs of their country's ideology. The result, especially in totalitarian countries, is that the state essentially teaches students to become stubborn nationalists. Thus, each nation teaches (brainwashes) all of its citizens a strict dogma. If the dogma conflicts with the dogma of another country, greater conflict can occur. So, not only is this danger to intellectual freedom, it also increases the potential for warfare: one intolerant generation teaches another to be as, or more, intolerant.
Russell notes that some knowledge should be required in any country: math, reading and writing. Teachers can and should be allowed to think and teach outside of any partisan, dogmatic, or narrow-minded thinking. If allowed to occupy this position, teachers are better able to instill free thought in their students and this will create an intelligent citizenry rather than a one-sided (and potentially bigoted or even racist) citizenry. This is why Russell calls teachers the "guardians of civilization."
The teacher should present all sides of an issue and give the students the same sense of intellectual freedom that he/she enjoys.
Russell then defines what "civilized" means by placing less emphasis on industry and technology, with more emphasis on citizens being enlightened, curious, and aware of the world around them. Unlike the propagandist who trains his students to be mindless slaves of the state, an effective teacher has a genuine desire to teach his students to be intelligent and free-thinking.
Russell adds that teachers are overworked and must spend too much time on examination material rather than on thought-provoking exercises. A further problem is that those who come up with the exam material are often administrators, not teachers, those who are out of touch with the students and education in general.
Ideally, the education system needs to be free from national/state ideologies.
This involves a deliberate restraint on the part of those who have power, and a conscious realization that there are men to whom free scope must be afforded.