Sources of lore

This is the way I see to be the quickest path to acquire Lore:

1. Keep buying everything from Morland's Shop. It will keep bringing books to study that will become Lore.
2. When Morland's shop closes, start buying books at Oriflamme's Auction House until it doesn't have any more books to sell. Oriflamme can also be found by a believer Exploring.
3. If you Explore with Secret Histories Lore, they will convert into Aspect: Location+Vault. Those might bring back more Lore. Here is a comprehensive description and requirements for all expeditions.
4. Dream with Passion and in the slot add a Lantern or Knock Lore. It will bring you Way: The wood. This guide at The Mansus section has a great explanation on how to open each location further and what you will find there. The idea here is to grab all the Secret Histories you can find and transform them into expeditions (as commented above). Expeditions bring a lot of Lore.
5. If you already made/have all the expeditions of a certain level (they start to repeat the location), start to "merge" the same Secret Histories to get advanced levels of them.
6. Some Lore books need to be translated. Some Patrons can translate those books if you pay them with Spintria. Patrons pays their commissions with Spintria or you can get it from expeditions. You will have to summon Teresa, King Crucible and Ezeem to learn Fucine, Deep Mandaic and Phrygian respectively.

maybe this will help:

Lore Fragments are a resource that can be obtained from studying some books, and some interactions. They can be upgraded by studying it with a fragment same aspect and level(or, for knock fragments, upgraded with any same level fragment except for secret histories). All fragments(except Secret Histories and Knock) can be subverted into another type of lore.

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