My attitudinals! All mine! (And you?)

A common pitfall to avoid is trying to specify whose attitude the attitudinals express. The reason UI cmavo are so simple is that they express direct emotional responses — gut reactions, without making any fine distinctions like whose attitude is involved. The reaction is always taken to be the speaker's. So .ui do cliva means you're happy that someone else is leaving, just like "You're leaving — Yay!" does. If you wanted to say that the 'someone else' is happy, not you, then you wouldn't say "Yay!" at all. Instead, you'd say something like "You must be happy you're leaving." The same goes in Lojban: if you're relaying someone else's responses, not your own, then that's what bridi are there for.

You wouldn't likely make this mistake for .ui; but there are other cmavo it's almost impossible not to do this with. The worst offender is probably .ei, which expresses obligation. .ei mi cliva means "I ought to leave." But .ei do cliva doesn't necessarily mean "You ought to leave." It's more like "I feel the obligation for you to leave": I can say this if I want you gone while you're making yourself comfortable — but not if you've remembered you've got to be somewhere else, while I'd want nothing more than for you to stick around.

Tip: The temptation to use attitudinals for others' reactions is strong enough, in fact, that there are a couple of ways of getting around it. If you add the UI5 cmavo se'i, you say that you feel the emotion for yourself. If you add se'inai, then, you say that you feel it for someone else: .uise'inai is pretty much "I'm happy for you!" And if you add dai, you're saying that the emotion is someone else's, and that you are empathising with them. If .a'u is "That's interesting!", .a'udai is more like "That must have been interesting for you!"

One final thing: if you want to know how someone feels about something, once again Lojban provides a fill-in-the-slot question word. The word asking the listener to fill in the attitudinal that best applies is pei. You can fill pei in with anything from selma'o UI, NAI or CAI. So if I ask you

.i pei le lunra cu blanu 
The moon is blue — how do you feel about that?

at least one response is .ienai "Disagree!" ("Uh-uh", "No way!", "No!", etc.) pei can also explicitly ask for NAI or CAI alone, by following a UI cmavo. So a response to

.i .u'ipei do farlu le pesxu 
You fell into the mud! Funny, eh?

could well be ru'e: "Kinda..." Then again, it could also be naicai: "Absolutely not, and I shall thank you never to mention it in my presence again." (Allowing for some latitude in translation...)