因

Denotes a relationship of dependency or derivation. Core senses include:

• Causality/Reason: The trigger or justification for an action.
• Occasion/Basis: Using a circumstance as a springboard or means to achieve something else ("by means of" or "taking advantage of").

• Verb: In older texts, functions as "to base oneself on," "to follow," or "to rely upon," typically followed by an object serving as a foundation.
• Preposition/Conjunction: Used both causally ("Because of [X], [Y] occurs") and instrumentally/opportunistically ("Taking [X] as an occasion, I do [Y]").
• Noun: The abstract concept of "cause" or "reason," often appearing in pairings regarding cause and effect.

Contrast with 由 (yóu): While both relate to origins, 由 typically suggests a trajectory, path, or point of origin ("from which"), whereas 因 suggests a prerequisite, dependency, or trigger ("the basis upon which").

Fanqie reading: 於眞; Tang-period reading: *qin.

Avoid an over-reliance on the modern translation "because." If a causal rendering feels logically strained in context, test whether the glyph is functioning as "taking as a starting point" or "on the occasion of."