What's the difference between using the potential form of a verb with よう and ため


For example:

[code]

    なるように - So that it will become
    なれるように - So that it will become
    なるために - So that it will become
    なれるために - So that it will become
    
[/code]

Well, they all mean the same thing




## なれる and なる

I think we should first get the difference between なれる and なる figured out. I'm
sure you know that なれる is the potential form of なる. Your translation does not
capture this very well.

なるように means "so that it will become."  
なれるように means "so that it **can** become."

I think there is a big difference between the two of these phrases. Here are
some phrases I pulled from this
[Chiebukuro](https://detail.chiebukuro.yahoo.co.jp/qa/question_detail/q1134114486)
post.

> 幸せになれるように、神様にお願いします。  
>  I prayed that I could become happy.

> 幸せになるように、神様にお願いします。  
>  I prayed that I would be happy.

There is a big difference between these two sentences. The author of this post
notes that the first one means that person prays to god so they **can** become
happy. It implies that they are praying for an environment in which they are
capable of becoming happy, but ultimately it is up to themselves to work
towards that goal.

The second sentence however, is a straight up wish that god will make them
happy. The person who is praying plays no part in that wish.

So, what comes after なれるように might _indirectly_ cause what comes before it
while なるように is a direct cause. This is not an absolute rule, but that's what
the "can" in "can become" implies.

## ために and ように

Note that this is also described [in this
post](https://japanese.stackexchange.com/questions/12450/difference-
between-%E3%81%9F%E3%82%81%E3%81%AB-and-%E3%82%88%E3%81%86%E3%81%AB). I'll
give a shorter version.

The biggest difference between these two is volition (and that ように has a lot
more uses). ために expresses that you have control over a situation while ように
means you do not. Finally, the [agent in the clause before ために and the agent
after must be the same](https://www.imabi.net/inorderto.htm). Here's an
example:

> ✕忘れないためにメモしておく。  
>  ◯忘れないようにメモしておく。  
>  Leave note so that (I) don't forget.

In this situation, you cannot use ために because you don't control whether you
forget something or not. Forgetting is something you don't do on purpose.
However, you can leave a note with the _intention_ of making sure you do not
forget.

Maybe a more intuitive way to remember this is that ために is similar to "in
order to" while ように is closer to "so that".

## Conclusion

I'm sorry if this got a little long winded, but the difference between ために and
ように is difficult to explain without context. This might be a more suitable
translation, but it doesn't really address the nuances.

> なるように  
>  なるために  
>  so that it will become.  
>  in order for it to become.

What really matters is what comes before and after these two phrases. You
cannot use ために in a situation where the subject of the sentence does not
control the situation.

> 生徒が分かるように説明します。〇  
>  生徒が分かるために説明します。☓  
>  To explain so that the students understand.  
>  To explain in order for the students to understand. (?)

Although I know this example does not use なる, it expresses the same difference
between the two phrases. The second sentence is invalid because the subject in
the first clause is 「生徒」 and the subject in the second is the speaker. The two
subjects are different. What's more, the speaker does not control whether
students understand or not.

I hope this helps.

