Learn Hardcore Japanese: sono syousetu wo yomu to, aite no kimoti ga yoku souzou dekiru. - When I read that novel, I can clearly imagine how the other person feels.

It describes a natural or automatic result:
- その小説を読むと、相手の気持ちがよく想像できる。
  → When you read that novel, you can (naturally) imagine the other person’s feelings.
It’s often used for:
- general truths: 春になると、暖かくなる。
- stable cause–effect: このボタンを押すと、ドアが開く。
It’s usually not used when the second part is a voluntary action or request by the speaker (like “When I get home, I will call you”) – for that, you’d more often use 〜たら or 〜ば.

Why is it 読むと and not 読んだら? What is the nuance difference between と and たら here?

Both are grammatically possible, but the nuance differs:

読むと:
- Emphasizes that whenever you read that novel, the result naturally happens.
- Sounds more like a general rule / typical effect of that novel.
読んだら:
- More like “if/when you (happen to) read it (at some point), then you’ll be able to imagine the other person’s feelings.”
- Often used for one-time events, future conditions, or more subjective situations.

So:

その小説を読むと、相手の気持ちがよく想像できる。
→ That novel is written in such a way that, as a rule, reading it makes the other person’s feelings easy to imagine.
その小説を読んだら、相手の気持ちがよく想像できる。
→ When/if you read that novel (on some occasion), you will be able to imagine the other person’s feelings.

The original sentence sounds more like a general characteristic of the novel.

Who or what is 相手 here? Does it mean “the other person in the novel” or “the person you’re dealing with”?

相手（あいて） literally means “the other party / the other person (relative to you)”.

In this sentence, it could mean:

the person whose feelings are being understood thanks to the novel
depending on context, it might be:
- a character in the story
- your conversation partner, lover, opponent, etc.

Japanese often leaves context implicit; 相手の気持ち just means “the other person’s feelings” and which person that is would be clear from the surrounding discussion.

What is the function of の in 相手の気持ち?

の here is the possessive / attributive particle, similar to English ’s or “of”.

相手の気持ち = “the other person’s feelings” or “the feelings of the other person”.

Structure:

相手 = the other person
気持ち = feelings / emotions
相手の気持ち = the feelings that belong to / are held by that other person.

Why is が used after 気持ち (相手の気持ちが) instead of を?

This is because of the verb phrase 想像できる (“can imagine”).

With potential forms (verbs meaning “can do X / to be able to do X”), Japanese normally marks the thing that is possible with が, not を.

Pattern:

Xができる = can do X / X is doable
泳ぐ (to swim) → 泳げる (can swim): 私は泳げる。
理解する (to understand) → 理解できる (can understand): 日本語が理解できる。

In the sentence:

相手の気持ちがよく想像できる。
- 相手の気持ち = what can be imagined
- So it becomes the subject with が, not an object with を.

If you used a non-potential construction, you’d more likely see を:

相手の気持ちを想像する。 = (I) imagine the other person’s feelings.

What exactly does 想像できる mean? How is it formed?

想像できる（そうぞうできる） means “can imagine / be able to imagine”.

Formation:

想像する = to imagine
できる = can do / is possible
想像することができる = can imagine (literally “the act of imagining is doable”)
In normal speech, 〜することができる often shortens to 〜できる:
- 想像することができる → 想像できる

So 想像できる is basically the potential form of “to imagine”.

What is the role of よく here? Does it mean “often” or “well” or “really”?

よく has multiple meanings depending on context; here it means “well / easily / really”, as an intensifier.

相手の気持ちがよく想像できる。
→ You can really imagine / clearly imagine / easily imagine the other person’s feelings.

It does not mean “often” in this sentence. The “often” meaning appears mainly with frequency, like:

よく映画を見ます。 = I often watch movies.

Here, because it modifies 想像できる (a mental ability), “well / clearly / very” is the natural reading.

Could the sentence also be よく相手の気持ちが想像できる? Does changing the position of よく change the meaning?

Yes, よく相手の気持ちが想像できる is also natural.

In practice, both:

相手の気持ちがよく想像できる
よく相手の気持ちが想像できる

convey essentially the same meaning here:

You can really / clearly imagine the other person’s feelings.

Nuance: Japanese word order is relatively flexible. Moving よく slightly can give a tiny focus difference (what is emphasized), but in this sentence everyday speakers would not feel a strong difference. Both are fine.

Why is the verb 読む in plain present form? The action “reading that novel” might be in the future; why not a future tense?

Japanese does not have a dedicated future tense. The plain present form is used for:

present
future
habitual actions
general truths

In その小説を読むと, it’s describing a general condition / rule:

Whenever (now or future) you read that novel, X happens.

So 読むと naturally covers “when you read (now or in the future)” without needing a special future form.

Who is the subject of 読む and 想像できる? There is no explicit I or you in the sentence.

Japanese often omits the subject when it’s clear from context.

In this sentence, the implicit subject for both actions is usually:

“you” in a general sense (like English “you” = “one/people in general”), or
sometimes “I”, depending on context.

So it can be understood as:

When you read that novel, you can really imagine the other person’s feelings.
or
When I read that novel, I can really imagine the other person’s feelings.

The choice depends on whose experience is being discussed in the wider context.

Could we say その小説を読めば、相手の気持ちがよく想像できる。 instead? What’s the difference between 〜と and 〜ば here?

Yes, その小説を読めば、相手の気持ちがよく想像できる。 is grammatically correct and natural.

Nuance:

読むと:
- Feels more like a fixed, automatic result whenever that condition is met.
- Very suitable for general tendencies or stable cause-effect.
読めば:
- Also conditional, roughly “if you read it”, but can feel a bit more like hypothetical or conditional advice.

In this particular sentence, the difference is subtle; both are acceptable. 読むと just leans slightly more toward “That novel is (by nature) written so that reading it makes the other person’s feelings easy to imagine.”

The sentence ends with できる in plain form. How would I make this sentence polite?

To make it polite, change the final verb to its ます-form:

Plain:
- その小説を読むと、相手の気持ちがよく想像できる。
Polite:
- その小説を読むと、相手の気持ちがよく想像できます。

Everything else can stay the same; you just adjust the final verb to match the desired politeness level.