Polaris:Why is this such an issue? We can say "live each moment with gratitude" or "live your life one day at a time", can't we? Who declared (and where is it written) that vivi can only be intransitive?

I believe the issue lies in the notion of the action of living having a direct object, and thus some would prefer it to be intransitive (or it's officially intransitive) because of the chance that someone might go "How can you live something?" (A bit like "how do you die something?", a question I remember having as a child when I first found out about dyes...)

After all, "live every moment with gratitude" is "live + adverb (at every moment) + adverbial phrase (with gratitude)". And "live your life" technically could be phrased another way, e.g. live with your life, do your life, etc, although "live your life" I don't think will cause any problems simply because it's more straightforward.

Any deeper however, and then it's possible that a discussion about whether the accusative and nominative are actually a type of adverb as well will come up, and then whether the verb is really an adjective describing the state of the nominative, and then whether it's all meaningless, well, it'll just get messy . But that's why I think it's treated intransitively, because there's nothing the adverb can't really do in that situation, and because anything the accusative can do, it could do so while possibly confusing some people.

After all, "live every moment with gratitude" is "live + adverb (at every moment) + adverbial phrase (with gratitude)". And "live your life" technically could be phrased another way, e.g. live with your life, do your life, etc, although "live your life" I don't think will cause any problems simply because it's more straightforward.

Hey, Chrisso---it is very astute of you to see that "live every moment" is, essentially, an adverbial expression of time (live AT every moment). That had completely escaped me. In the expression "to live one's life", the word life is a cognate object (live and life are forms of the same word root), so technically, that wouldn't count (many intransitive verbs can take a cognate object and still remain intransitive verbs).

However, the English word "live" is, most definitely both instransitive and transitive, according to the dictionary.
I can live my life (cognate object), of course, but I can also live my beliefs, live my years, live a double existence, etc. True, I CAN reword some things as an adverbial phrase, and I can make some of these ideas part of a prepositional phrase---but I don't have to. English allows "live" to be a transitive verb.

My question is simply this--where is it written that Vivi (in Esperanto) can only be intransitive? Are we only supposing that it is? Where would one find the official status of this (and other) word roots printed?

Great examples of words that need a transitive use of "live" in English. It is quite a complex relationship for many of them, since in relation to things like "live my years", there's both a person living and a thing being lived out. I can't think of a decent alternative anyway. (living out beliefs probably does have one, e.g. kun or je, but the notion of living out ones years seems a bit more complex to me).

RE who's making the decisions, I have no clue Reta vortaro lists "vivi" as intransitive, and this site (3rd "vivi" down using ctrl+F) also mentions the apparent intransitivity of "vivi" (and talks about the cognate objects you mentioned then - thanks for mentioning them too, I found it to be a learning experience nonetheless!)