Why are spelling conventions in English so peculiar, such as with the silent “b” in “doubt”? It’s due to the influence of Latin culture and symbolic capital. Symbolic capital describes the immaterial resources that people draw on in order to maintain or improve their social status. Language, literature, the arts and other forms of culture act as symbolic capital that signal our belonging to a particular class. Language and culture are also used to elevate the authority and economic achievements of dominant groups.
Throughout history being able to speak and write Latin has been a sign of being upper class. Latin was also important to the religious elites who acted as scribes that documented culture and history.
Latin drew on French language rules as French grew out of Latin. The French word for doubt has a “b” which is why Latin scribes used it when they started to catalogue English in written texts. English is a Germanic language that was spoken by the masses long before it was written down and so the elites reflected their own linguistic norms on the English written form rather than following the spoken rules.
This Chalking Points video documents this history on brief.
The Other Sociologist 
I think there is a small mistake in your post: there’s no “b” in the French word for doubt. It disappeared from Latin to French. But English scribes took it back from Latin.
There seems to be extra complication. As opposed to the old French word for “subtle” that has no “b” (“soutil”), the current French word is “subtil”…
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Hi Romain Brasselet It’s discussed in the video. The insertion of the “b” wass made by 15th & 16th Latin scribes.
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