Help me wrap my head around this

[Rod Wadd]

できない約束しても、守れっこない。

The way I understand this is "Even if you make an impossible promise, it's impossible to keep."

Usually when I encounter "しても" it has a sense of "even if" or "no matter what/how." For example, たとえ食べても、おなかがはらない。　No matter how much I eat Idon't get full. In other words, contrary to expectation. But in the example above, it seems as though "できない約束”　and "守れっこない" do not have the same sense of being contrary to expectation. It seems natural that you wouldn't be able to keep a promise that you can't keep Can anyone help me figure this out?

Thanks in advance!

[hatch_jp]

It's not always true that "～ しても" can be translated into "even if" or "no matter what/how"
I think this kind of sentence is simply hypothetical.
In this case, I think "～ しても" means just "if".

できない約束しても、守れっこない。
If you make an impossible promiss, it won't be kept.
You won't keep a promise that you can't keep.

努力（どりょく）しても、無駄（むだ）だ。
If I make an effort, it will be in vain.
My effort will be in vain.


Ummm, I don't think my explanation is good, so please refer to the following site. There are many examples that "～ても" is not translated into "even if"
http://eow.alc.co.jp/%e3%81%a6%e3%82%82%e3%80%81/UTF-8/

[Rod Wadd]

Hatch, thank you for your reply.

I　feel as though your example, 努力しても、無駄だ does have a sense of "even if" in English. 　

Even if I try/no matter how I try . . . it will be in vain.　In other words, you will fail regardless of effort, as opposed to because of it.

My original sentence still seems to me to be more like 　努力しても,成功する。　Where the part following しても　is similarly counter-intuitive.　

Otherwise, are できない約束しても、守れっこない　and　できない約束したら、守れっこない　the same? If not, how are they different? Is the second sentence even proper Japanese?

Sorry if I'm just being a bit thick here . . .

[Psy]

I think you might be putting the two clauses too close together in your head. 約束をしても、守れっこない alone makes sense, right? Even if one made a promise, it couldn't be kept. If you make it できない約束 it means a promise that can't be, but the focus of the clause is still on the promise, not the fact that it's an impossible one. So できない約束をしても、守れっこない even if you were to make the impossible promise, it couldn't be kept.

To me, the difference between できない約束しても、守れっこない　and　できない約束したら、守れっこない is that the first one expresses, in a hypothetical sense, that even if the promise were made, it would be impossible. The second simply states the fact that one can't keep impossible promises. They both mean "if," but express it in different ways. I can't vouch for how natural the したら sentence sounds, seeing as in Japanese grammar tests I took the correct answer was しても for such situations. Still, it seems plausible that either one could be used depending on the situation.

That's my take anyway.

[Rod Wadd]

Psy, thank you very much. That makes perfect sense.