"Being" is not used when the adjective describes a current static state, eg. " The state can be temporary. I am cold.
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.
AlpheccaStarsI am serious. (I am not joking.)XX I am being seriousI am being serious is possible in British English. There are a few dozen citations for BE being serious in COCA, suggesting that quite a few Americans think it's acceptable.
fivejedjonI am being serious is possible in British English.5JJ; I was trying to make a black and white distinction for the poster's clarity. The boundary is sometimes gray, though, depending on personal speech patterns.
DanilWhat is the difference between 1) I am serious.2) I am being serious.This is a case of "trait" versus "state".