Dirt and earth are synonyms . Or in this case, dirt and erf.
Are dirt and erf really synonyms? I'm not so sure. Consider Book 0, Episode 1
"This thread was being drawn up by the system of the world. Thinkamancers knew it as a 'Grandiocosmic string.' Its numbers were being shaped and guided by the firmament, by what magic theorists called the Erf Axis."
This makes it sound like Erf is the firmament, totally opposite to dirt. I have no idea what the firmament has to do with any of this, but there it is.
Dirt and earth are synonyms because earth is literally Earth. So yes, dirt and erf are synonyms, due to the location being Erf. And I have no idea what the firmament has to do with anything either, because it certainly isn't applicable to what we are talking about. Dirtamancy is Erf aligned, so I know you aren't arguing that that dirtamancy and the Erf axis are unrelated.
Firmament means "vault of heaven" or "sky." In this context, it clearly means the former. And since the thread is described as traveling upwards, the firmament could be Erf itself and not be contradictory.
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