Metsis:Altebrilas,

Ĉu vi legis mian skribaĵon de sur la unua paĝo?

La signifo de iĝ-verbo dependas de tio, kia la sen-iĝa verbo estas. PMEG listigas kvar kazojn.

Ekzemple enamiĝi apartenas al la unua grupo, ordinaraj IĜ-verboj.
 

• …ke vi enamiĝis en min

"Vi" estas la subjekto kaj estas tio, kio eniras en novan staton, de ne-amo ĝis amo.

La dua grupo, iĝ-verboj faritaj el objektaj verboj, ankaŭ estas kutima. Mi ne posedas la francan, do mi ne scias, kiel oni esprimas la diferencon:
 

• (a) Li malfermas la pordon / (fi) Hän avaa oven / (en) He opens the door
  
• (b) La pordo malfermiĝas / (fi) Ovi avautuu / (en) The door opens

Kaj Esperanto kaj la finna, sed ne la angla, uzas apartajn verboformojn por montri diferencon inter (a) iu nomata kaŭzas la malfermadon kaj (b) io nespecifita (ekz. vento) kaŭzas la malfermadon.

Dankon pri via detala klarigo. Mi legis la unuapaĝan mesaĝon, sed tio ŝajnas al mi iom komplika por "simpla lingvo", kiel ni prezentas Esperanton.

X-iĝi = iĝi X-o

X-iĝi = iĝi X-a

X-iĝi = iĝi X-ita

ŝajnas al mi sufiĉe simpla por komencantoj. Aliaj kazoj estas evitindaj, do "eksidi" preferindas al "sidiĝi".

sergejm:Espels, vi indikis ke vi estas el Rusio. Verŝajne, vi estas ruso aŭ almenaŭ scias la rusan.
Espels, you are from Russia, so I think you know Russian.

Mi fermas la pordon - La pordo fermiĝas.
Я закрыл дверь - Дверь закрылась.
Mi amas ŝin - Mi (ne ŝi!) enamiĝis.
Я люблю её - Я (не она!) влюбился.
iĝ laboras simile al la rusa ся!
iĝ works as Russian ся!
There is no patterns in Esperanto as in programming language!

Спасибо за ответ.
Изначально, вопрос был про amigxas, а не enamigxas. С enamigxas более менее понятно.
Mi amigxas.
Я любился (например, ей). Мы не говорим так на русском, но если спросить любого, он скажет, что смысл понятен. - Меня кто-то любил.
Я нравился ей. - совсем хорошее русское предложение. Она испытывала ко мне чувство, которое можно назвать "нравиться. Один в один аналог "любился" по конструкции.

А вот, например, предложение из wiki: (хоть и в категории устар., но смысл абсолютно ясен)
"Не любилась ему жена, хотя и молодая была баба, красавица, на коей он в третий раз женился, потому, значит, что она лесничему просто прислуживала."
Не любилась ему жена - жена не была любима им.

Thanks for your response.
My first question was about "amigxi". I understand more or less about "enamigxi".

Я любилСЯ ей (mi amigxas). It is not an ordinary sentence, but the meaning is understandable, at least one can imagine what it means.
Я нравилСЯ ей. She liked me. It is exactly the same pattern as "Я любился ей". I was loved by her.

This one from wiki, it is not modern russian language, but still make sense:

"Не любилась ему жена, хотя и молодая была баба, красавица, на коей он в третий раз женился, потому, значит, что она лесничему просто прислуживала."
Не любилась ему жена - His wife was not loved.

Altebrilas:
Dankon pri via detala klarigo. Mi legis la unuapaĝan mesaĝon, sed tio ŝajnas al mi iom komplika por "simpla lingvo", kiel ni prezentas Esperanton.

Nedankinde. Vi pravas, ke Esperanto havas trajtojn, kiuj aperas nesimplaj al tiu, kies denaska lingvo malhavas tiajn trajtojn aŭ oni ne vidas konekton al iu denasklingva trajto. Ŝajnas, ke la iĝ-verboj estas unu el la tiaj.

Despite the fact that in modern Esperanto dictionaries, the entries are organised alphabetically by root, the definitions relate to words, not roots. After all we speak in words, not roots

Ordinarily the derived compound words will reflect the meaning of the head-word (the one at the top of the dictionary entry). However this is not absolute..

For example in enamiĝi the am reflects the meaning of amo, not ami.

The translation of our friendship became love is not naturally rendered by nia amikeco amiĝis.

And the reason for this is there does not seem to be any good reason from current and previously established usage, or from the internal structure of the compound, or from analogy with other compound words of a similar structure that are also derived from a verbal head word, to force the am to stand for amo.

Sudanglo, thanks for your response I get it.
But how went that "am" reflected to "amo" and not to "ami". In the case with enamigxi I can accept that, but in simple word "ami" how it could occured. I mean the dictionaries are solid and you can get the answer from them. One can say something reflects to this word, the other - "No, you are wrong. I think the opposite, your opinion does not make any sense to me". What can they do? They can check the dictionary.
But your response give the option to everyone decide himself, as he thinks should be. Seems to me it can create chaos.

The key element in my comment is that ordinarily the derivations relate to the definition of the headword in the dictionary. It does not lead to chaos that In some compound words this is seemingly not the case.

As a previous poster said, Esperanto compound words have to make sense - have to relate to something in the world that people talk about. Otherwise they won't get used. Pragmatism prevails rather than the complex edifice constructed by grammarians.

If I understand you correctly, you have no problem in accepting that the analysis of enamiĝi makes more sense if you see it as iĝi en amon.

But really the issue here is do you immediately see what in the real world enamiĝi is referring to. If so, we can leave the analysis to the pedants and the grammarians.

Consider enveniĝi kaj endormiĝi. How to analyse?

The head words in the dictionary are respectively veni and dormi. But whilst you will find lower down a definition for enveni, you won't find a definition for endormi (people don't commonly say mi endormas).

So you might analyse enveniĝi as enven(i)iĝi and endormiĝi as endorm(o)iĝi . But all that really matters is - is it obvious what enveniĝi and endormiĝi mean..

sudanglo:The key element in my comment is that ordinarily the derivations relate to the definition of the headword in the dictionary. It does not lead to chaos that In some compound words this is seemingly not the case.

As a previous poster said, Esperanto compound words have to make sense - have to relate to something in the world that people talk about. Otherwise they won't get used. Pragmatism prevails rather than the complex edifice constructed by grammarians.

If I understand you correctly, you have no problem in accepting that the analysis of enamiĝi makes more sense if you see it as iĝi en amon.

But really the issue here is do you immediately see what in the real world enamiĝi is referring to. If so, we can leave the analysis to the pedants and the grammarians.

Consider enveniĝi kaj endormiĝi. How to analyse?

The head words in the dictionary are respectively veni and dormi. But whilst you will find lower down a definition for enveni, you won't find a definition for endormi (people don't commonly say mi endormas).

So you might analyse enveniĝi as enven(i)iĝi and endormiĝi as endorm(o)iĝi . But all that really matters is - is it obvious what enveniĝi and endormiĝi mean..

Lets take another example.
La tero turniĝas ĉirkaŭ sia akso. Turni - a transitive verb root. Does it mean that Earth becomes a rotation?
But in case with "ami" this pattern does not work. Amiĝi means "to become love", despite "Ami" is a transitive root too. Thats my point, and as you can see there is not compound words with preposition "en".
As the rules say: "An IĜ verb may also be made from a transitive verb. in this form of IĜ verb, IĜ doesn't indicate transition from one state to another. IĜ there only serves to make the verb intransitive, to change its role in the sentence"
malfermi → malfermiĝi = to become open, to be opened (by itself).
turni → turniĝi = to become turned, to be turned (by itself).
I just follow the rules:
Mi amiĝas, In my opinion it should mean: They love me, may be without my efforts for that.

La tero turniĝas ĉirkaŭ sia akso. Turni - a transitive verb root. Does it mean that Earth becomes a rotation?
But in case with "ami" this pattern does not work. Amiĝi means "to become love", despite "Ami" is a transitive root too. Thats my point, and as you can see there is not compound words with preposition "en".

First of all, all roots except the "memstaraj", don't belong to any part of speech, nor can they be categorised as "transitive", "intransitive", etc.
Turn' is not a transitive verb root. Turni, however, is a transitive verb.
Am' is not a transitive verb root. Ami, however, is a transitive verb.
However, in the Universala Vortaro, Zamenhof defined the root by syntactic words in the five languages of the dictionary. So, one could argue, that e.g. the "base" form derived from the root am' is ami, which is a verb. But let's not forget, that the verbal character doesn't come from "am", but from "i".

"Truni" and "malfermi" on the one side, and "ami" on the other side, are not directly comparable in the context of your question. The first two describe a change of state (from stationary to rotary; from closed to open), while the latter describes an action (if you like to look at the act of loving is an active process) or an unchanging state (if you see love not as an action).

As the rules say: "An IĜ verb may also be made from a transitive verb. in this form of IĜ verb, IĜ doesn't indicate transition from one state to another. IĜ there only serves to make the verb intransitive, to change its role in the sentence"

Where did you find this rule? Malfermiĝi does indeed indicate a transition from one state (closed) to another (open), we just don't know (or don't care) who or what caused this transition. Turniĝi indicates a whole set of minuscule transitions.
Also I think the "IĜ there only serves to make the verb intransitive" is a bit confusing. In the case of state-transition verbs, iĝ removes one argument (the cause of the transition) and we are left behind with only one (the patient of the transition). As a secondary effect, this sole argument moves into the subject position, because in Esperanto we generally can't have verbs without a subject (with the exception of verbs whose constant subject is implied).

These rules are from here, lernu grammar. You can find them yourself at "29. Suffixes" article.
In my opinion transition from one state to another is not "as be open or closed". Compare
Pala - paligxi.
Longa - longigxi.
Pinto - pintigxi.
But "fermigxi" does not mean become the close, it means "to be closed", that's the difference.
All words have roots and the roots are different. I thought it was a common fact. Why do you think the opposite? The main root is on the top of the dictionary's page. For example, it is obvious that akvo is a noun root and pala is an adjective. But with "Ami - Amo" you have to check a vortaro.

I already said, there is no patterns in Esperanto, except scolar rules, e. g. declination and conjugation.
There is principle 'neceso kaj sufiĉo':
La pordo fermigas = la pordo fermITiĝas = la pordo iĝas fermITa.
But you can insert AT instead.

Homo fermiĝas malantaŭ la pordo = homo fermANTiĝas malantaŭ la pordo = homo fermAS la pordon KAJ igas SIN fermITa malantaŭ la pordo.

Mi amiĝas = mi amANTiĝas = mi iĝas amANTa.

Computer can't predict which suffixes are ommited. But man can define them from context - he often even does not think about the ommited suffixes and simply understand.