A topic from AEG's L5R CCG Rules forum, copied for Oracle of the Void from a copy of the forum saved in October 2015, so pages it didn't save are missing. Players' names are left out; the rules officials are named. Rulings are as they stood on these dates; later rulings, the rulebooks and the Rules Archive may differ.
A player, 13 July 2010
Is it legal for The Thriving Light's reaction to reduce Only Actions Speak's honor negation to 0, thus bypassing the latter's effect?
Only Actions Speak Reaction: After an action is announced: Negate all Honor gains until after the action's resolution. At that time if this negated any gains, negate all Honor gains until the end of this phase and draw a card.
The Thriving Light Reaction: Before an action's resolution: Until that resolution ends, reduce the next Honor gain or loss by 5 (minimum zero).
Brook Cunningham (rules official), 13 July 2010
Is it legal for The Thriving Light's reaction to reduce Only Actions Speak's honor negation to 0...?
No. A negation isn't a loss or a gain.