Difference between —るのでは and —たのでは

Question

Are the following pairs of sentences equivalent?

1a そりゃ、落語を差向いで聞いたんじゃ、面白くもおかしくもない

1b そりゃ、落語を差向いで聞くんじゃ、面白くもおかしくもない

2a 店賃を払った上に小言を言われたんじゃぁ、間尺にあわねぇ

2b 店賃を払った上に小言を言われるんじゃぁ、間尺にあわねぇ

3a それでさ、こっちの人が食えてこっちの人の口に入らねぇってんじゃケンカになるだろ

3b それでさ、こっちの人が食えてこっちの人の口に入らねぇってったんじゃケンカになるだろ

4a おい、そんなインチキしたんじゃぁ本心が分からないじゃないか

4b おい、そんなインチキするんじゃぁ本心が分からないじゃないか

(1 is from 徳川無声, the rest, 落語.)

Answer 1

I once wrote an answer for this, which I admit was a little oversimplified. Whether or not you use た largely depends on how much the speaker feels the said event is "completed". In other words, whether the focus is a resultant state or the change in state (or will to change the state). When the event happens relative to now is not necessarily important.

• ～るのでは tends to be preferred when:
  • it is a habitual action
  • it explicitly involves someone's intention or state change ("is/was going to ..." or "will/would ...")
• ～たのでは tends to be preferred when:
  • it refers to an event that has already happened or finished
  • the focus is on the resultant state itself

This difference may or many not be important depending on the context. When comparing 4a and 4b, 4a sounds like you're referring to the resultant state the cheating has already caused, whereas 4b sounds like you're pointing out someone's intent to cheat. When comparing 1a and 1b, 1a sounds like it's describing the result that occurred after one specific event of listening, while 1b sounds like you're speaking in general terms. The same for 2a/b and 3a/b.

You can use た for future events, too:

1. その部品が1週間後に届いたのでは、3日後のコンテストに間に合わない。
2. その部品が1週間後に届くのでは、3日後のコンテストに間に合わない。

The condition part refers to a future event, but you can still use た, which is perfectly fine. The difference is negligible in this case, and these two are interchangeable.