I think that if these -antas, -intas, -ontis, etc forms were commonly used, we would all understand them more rapidly.

But they aren't used that much so people don't find them easy to parse instantly.

I don't think anyone has mentioned the other important principle, which is that in Esperanto, we value succinct speech and use of simple verb forms.

Therefore we prefer not to say "estos parolinta" in cases where we could say simple "parolos" with a few more words for context. These participle forms are in the language for a reason, and we do use them, but we use them much, much less than you might expect.

In English we distinguish between "I went", "I had gone", "I have gone", "I was going", etc. You can make all of these verb forms in Esperanto, if you want to. But in Esperanto normally we would just say "mi iris", even though it is possible to use a participle form to make it more precise. In Esperanto we prefer to look at whether all of that precision is truly necessary for a certain case. And if the precision is necessary, sure, we use a participle or we use some other time-related words to make the time clear and precise. And if the precision really isn't that important (usually it isn't), we use a simple verb form, -is, -as, -os, etc.

-----

On the difference between -as and -antas, I think there is a difference. -antas is something happening right now at this second. -as can be used for that meaning, but -as can also be used to describe something that usually happens (but is not necessarily happening right now.

Therefore I can say "Mia filo ne ploras" and it can mean either "My son doesn't cry [in general]" or "My son isn't crying [right now]". Context would tell you which meaning was intended.

"Mia filo ne estas ploranta" would only mean "My son isn't crying [right now]". The participle forces us to treat this as a strict present tense, rather than a generalized "things that usually happen" present tnese.

erinja:I don't think anyone has mentioned the other important principle, which is that in Esperanto, we value succinct speech and use of simple verb forms.

Therefore we prefer not to say "estos parolinta" in cases where we could say simple "parolos" with a few more words for context.

If you read carefully through all posts, you'll see that many of us have mentioned that. Thanks for puting it into more precise words.

Volapük is easy!

The point I wanted to make was that if you assign different meanings to -as and -antas, you cannot do the same thing with -atas. Here's an example of the asymmetry:

Li helpas la knabon = he helps the boy (habitually, maybe not right now though)

Li estas helpanta la knabon = he's helping the boy (right now, but possibly as a one-off)

BUT

La knabo estas helpata de li = the boy is helped by him AND the boy is being helped by him (no idea regarding habitual or progressive nature)

Esperantists are seemingly not bothered about this, and the imbalance doesn't cause practical problems, but I still think it's an ugly situation. The solution is to just ignore -antas forms (likewise -antis and -antos).

Volapük and even Lojban verbs are easy and simple if used in that manner at least. Very powerful languages, both of them.
EO is the same too. And like someone to do with Spiderman says/said/might have mentioned in quick parlance, "With great power comes great responsibility".

Roberto12:
BUT

La knabo estas helpata de li = the boy is helped by him AND the boy is being helped by him (no idea regarding habitual or progressive nature).

The problem is irrelevant. We can always say:

La knabo estas nun helpata de li.
La knabo estas kutime helpata de li.
La knabo estas ĉiam helpata de li.
La knabo estas nur malofte helpata de li.

But instead of the passive voice I would prefer:

Li helpas la knabon.

Frequent passive voice is natural to English, but in other languages it is used not so often (Polish for example avoids passive voice where possible).

Robert, you propose a solution. But there isn't a problem.

With another thread in mind, you could say we don't need rivolui or rotacii because we have turniĝi, but these terms allow further precision in the same way 'ant' allows us to be more precise than 'as'.

An if 'at' covers two meanings in the way that 'as', does then so what. Am I bothered?

If Esperanto makes finer distinctions in its active forms (which are much more frequent) then its passive forms, I don't think we need to describe the situation as ugly.

By the way, do away with 'ant' and you won't be able to say 'Promenante en la parko, mi renkontis Johanon'.

I concede that by circumlocution you can solve the "problem".

(I'm not saying -ant should be scrapped.)

So there's nothing wrong with it, it's just generally avoided because it's not common usage.

What about with other adjectives? Would people understand you if you said "mi bonas" in place of "mi estas bona"?

Echo49:So there's nothing wrong with it, it's just generally avoided because it's not common usage.

What about with other adjectives? Would people understand you if you said "mi bonas" in place of "mi estas bona"?

I write it again. There are no pure adjectives, substantives or verbs in esperanto. There are roots that can be used as such by adding a proper ending.

bon|a = is adjectival root
bon|i = verb
bon|o = substantive
bon|e = adverb

So almost any root (when it is sensible) can be transformed into any part of speech when necessary (logic is best guide here). But be careful. Adjectival roots used as verbs generally mean:

to be such

fort|a = strong
li fortas = li estas forta

blu|a
la floro bluas

but the roots can be also verbial, and then such verb means an action. Always check with your dictionary.

bol|i = verbial root = to boil
la akvo bolas = la akvo estas bolanta

mov|i = verbial root
li movas rapide = li estas movanta
li estas mova = he is mobile/active/agile/lively...

"Mi bonas" is perfectly correct and it means the same as "Mi estas bona"

Take note that this doesn't mean that you are doing fine (that would be "Mi fartas bone"). It would mean "I am good", as in, I am a good person.