rosto:Although -iv- is not an official suffix, you can find it in dictionaries. Why not to use it or some other inofficial which is in a dictionary? Is Esperanto a live language or dead one?

I didn't say you shouldn't use it, I said I'd rather not use it. Firstly because it's not official, and secondly because it's not necessary. The fact that it is mentioned in some dictionaries only means to me that those who composed the dictionaries feel it's fair to let you know about it.

There are things in Esperanto I do not like, and there are a few cases in which I bend its rules when they don't seem logical to me. But in this specific case I think that E-o provides a fine solution already and there is no need for a further suffix.

Whether iv should ever be used is a good topic for a debate, like the use of ujo versus io for the names of countries. The case against is well made by mnlg, and authorities like PMEG.
On the 'for' side, Kalocsay and Waringhien's Plena Analiza Gramatiko(section 354) suggests that one good place for iv is with verb-adjectives, where the result is used in a passive sense, e.g. ĉagreniva, konfuziva, konsterniva.

Miland:
On the 'for' side, Kalocsay and Waringhien's Plena Analiza Gramatiko(section 354) suggests that one good place for iv is with verb-adjectives, where the result is used in a passive sense, e.g. ĉagreniva, konfuziva, konsterniva.

I see nothing about these constructions that would logically prevent you from using ĉagrenpova, konfuzpova, konsternpova, etc. And indeed, if something is annoying, confusing, or consternating, why not ĉagreniga, konfuziga, konsterniga?

I am mainly against use of -iv- because I see it as unnecessary. I can choose konfuzpova if something could potentially cause confusion, or konfuziga if it does cause confusion. What do I gain with -iv-? I don't even lose a syllable by using it. I have yet to be shown an -iv- word that has a meaning that I can't generate using existing endings (not to say that such a word doesn't exist, but I haven't seen one yet).

Other people can use -iv- if they want to, but I never use it myself. I see its use as somewhat lazy, much like using "ain't" instead of "isn't" or "aren't". (and "ain't" is also found in the dictionary)

K&G say that ig is a wrong substitution for iv, so that ĉagreniga is not the same as ĉagreniva. As to why one might prefer iv to pov, we have Occam's razor, that entities should not be multiplied beyond necessity. Here I apply the principle not to the number of suffixes but the addition of the abstract notion of 'power' inherent in pov. 'Confusing' (potentially) is not quite the same thing as 'having the power to confuse' , just as what a thing is is different from what it has, even if the difference doesn't matter much in practice. John Wells in Part 2 of Jen Nia Mondo finds iv sufficiently worthwhile to mention it in section 13 of the last lesson 25, so that kreiva is renderd 'creative'. So it's something that people should know about, even they don't use it.

Wouldn't Occam's razor in this case tell us that greater simplicity is in *not* creating a new ending?

In any case, I see no problem the idea of "power" in the root of pov-. The Merriam Webster dictionary gives the following definitions of "creative":

1: marked by the ability or power to create : given to creating

(this would be "krepova" or even "kreebla" in some contexts)

2: having the quality of something created rather than imitated : imaginative

(this would be "kreita" or in some contexts, krea)

3: managed so as to get around legal or conventional limits ; also : deceptively arranged so as to conceal or defraud

(This would simply be "ruza" in Esperanto, I think)

How is being confusing different both from having the power to confuse, and from being something that actively confuses? And is this difference important enough to be worth creating a whole new suffix to make this distinction? For example, Esperanto has just one word for "cat" that doesn't make any distinction between small housecats and large jungle cats, except through the use of adjectives. Does this mean that Esperanto is lacking because it has just one word for these two concepts that (in my mind) are far more distinct than the fine shades of meaning in "confusing"?

I don't doubt that people should know about the suffix -iv-, because it is used and they should recognize it when they see it. Similarly, in my opinion, learners of English should be familiar with the word "ain't" even though I would not recommend they use it.

It doesn't much matter to me what John Wells' opinion is on this. I have seen use of -iv- also in learning texts by Stefan McGill, while we're counting. You can find eminent supporters on both sides, but it doesn't mean that I want to use a suffix that I believe is unnecessary.

In any case, as with all linguistic points of contention, I think that each individual Esperanto speaker should carefully look at all sides of the issue and make a decision for themselves, to avoid making a decision based on their respect for a person who holds an opinion (rather than based on the merits of the opinion).

I see pov as adding an additional and unnecessary abstraction, and iv as being more reflective of something in itself. For this reason iv may be more useful both as a philosophical tool and poetically.
It is good to know that Wells or MacGill have spoken on an issue, because that is a signal that there is a view worth considering. I would certainly like to know how Stefam McGill uses iv, so as to understand better his reasons for using it.
It is good that we make up our own minds as to the usefulness and suitability of iv, in any particular situation. For me iv is less clumsy than pov, more beautiful and more suitable for poetry for that reason as well.

Miland:I see pov as adding an additional and unnecessary abstraction,

Ĉu vi ivas klarigi?

Miland:I see pov as adding an additional and unnecessary abstraction, and iv as being more reflective of something in itself.

How is "pov" more abstract than "iv"? Honestly I don't even know what "iv" means, and every definition I have ever seen for it (so far) has included the root "pov".

For this reason iv may be more useful both as a philosophical tool and poetically.

Since you have such a good understanding of "iv", what is the meaning of "konfuziva" that is not captured by "konfuzpova", "konfuza", or "konfuziga"? How would you personally define "iv"?

It is good to know that Wells or MacGill have spoken on an issue,

They have not spoken (to my knowledge), so much as used the suffix in their writings. At least in MacGill's case, I have only seen him use it, but not really discuss it. This may be a symptom of laziness more than anything else. And the -iv- suffix occurs mostly in the word "kreiva", as far as I see it. I think people are looking for a better translation of "creative" than "krea" or "krepova" or "kreema". I am not sure how "kreiva" is better than any of these, other than surface characteristics (i.e. both words end in -iv-).

'Eminentuloj' are subject to the same foibles as the rest of us.

And regarding creation of new elements of the language, I am far more open to creating new vocabulary words, as opposed to creating new suffixes. I think Ido suffered from an excess of unnecessary suffixes, making the language harder to learn. I am sure that someone saw each and every one of those suffixes as being essential and elegant and indispensable. I see -iv- as being in this category. People may see it as more elegant for poetry etc but this argument can be made ad infinitum, and I have seen very much fine Esperanto poetry that did not include -iv-.

As I indicated earlier, iv pertains to what something is in itself, whereas pov pertains to what something has (a specific power). Specific situations might make the notion of power unnecessary or even undesirable. I have written to MacGill to find out just how he uses it, and few other E-ists for their view on this interesting question. Kalocsay being one of E-o's most famous poets, and the author of an authoritative grammar, his mention of it is an indication that it is a worthwhile addition - for eminentuloj, it should not need stressing, are probably less subject to foibles than the rest of us in fields in which they are expert. iv arises from many roots that themselves end in iv, and so I see it as a natural development of a living language. Therefore, I do not reject its use altogether.

If -iv- "pertains to what something is in itself", wouldn't that be covered by the -a ending? And if not the -a ending, then what about -ec-, which expresses a quality of a thing? How do you distinguish between -iv- and these endings, and why is that distinction important? Something "kata" or "kateca" pertains to what a cat is in itself. Something "krea" pertains to the idea of creation. Right? And if not, then what does "krea" mean, in your opinion?

And in fact, every definition I have ever seen of -iv- has indicated that it indicates the idea of ability or capability (povo or kapablo, in Esperanto). pagi = to pay, pagiva = capable of paying. Therefore, "pagiva" has nothing to do with the internal quality of paying. It means the same as "pagpova" or "pagkapabla".

So I'm not really sure where your definition comes from, and would appreciate it if you could show me a source, because it is different from what I have seen and there is evidently some eminentulo's description of this suffix that I have missed somewhere (and which varies radically from what I have seen).

And since you are so diligent about contacting supporters of -iv- to find out how they use it, I assume you are equally diligent about contacting eminent opponents of -iv- to find out why they feel it's unnecessary, right?