got a problem with ought to

[ostap77]

"Under such an assumptiom, they ought to have arrived at completly different counclusions."

Is it OK with "ought to" here? If I say "under the assumption",I believe something to be true or probable as if I'm making a suggestion. "They ought to have arrived at ........" wouldn't mean either likelyness or probability in this sentence. It's more like they should have arrived at totally different conclusions but didn't.

[Tdol]

Ought to/should have arrived at completely different counclusions is fine, but I am not sure what you mean with Under such an assumption- who's assuming?

[ostap77]

Ought to/should have arrived at completely different counclusions is fine, but I am not sure what you mean with Under such an assumption- who's assuming?

I know you need more context. But sometimes we're given just sentences without any context to translate. So I was kind of hesitating whether "ought to" would fit in the sentence. I would most likely say something "they might have arrived" or "they could have arrived" to make an assumption since I can't tell if they arrived at totally different conclusions or not. 1)What does it mean in this sentence? Near as I can figure, "should" and "ought" can be used the following way "You ought to have moved to your knew appartment a month ago! Why didn't you do it yet?"
2) Is it like we thought they were going to do it but they didn't do it?

[bhaisahab]

"You should have moved to your new apartment a month ago! Why haven't you?"
This is much better IMO.

[ostap77]

"You should have moved to your new apartment a month ago! Why haven't you?"
This is much better IMO.

Pay it no mind it was just an example. What about question 2)? Does it mean they assumed they had done it but they actually didn't do it?

[bhaisahab]

Pay it no mind it was just an example. What about question 2)? Does it mean they assumed they had done it but they actually didn't do it?

It could mean that.

[ostap77]

It could mean that.

What I'm not getting is that why they use "ought to have arrived" to mean something they don't know yet? Why don't they use "might have arrived" or "could have arrived" to mean a degree of probability? They don't seem to know whether they've done it or not.

[Raymott]

What I'm not getting is that why they use "ought to have arrived" to mean something they don't know yet? Why don't they use "might have arrived" or "could have arrived" to mean a degree of probability? They don't seem to know whether they've done it or not.

"Under such an assumptiom, they ought to have arrived at completly different counclusions."
They* do know the conclusions that were arrived at. If they didn't, the sentence would read:
"Under such an assumption, they ought to arrive at completely different conclusions."

With the original sentence, they know the conclusions, and they believe that the conclusions should have been (ought to have been) different.

*They - the people making the statement; not the people who ought to have arrived at differernt conclusions.

[ostap77]

"Under such an assumptiom, they ought to have arrived at completly different counclusions."
They* do know the conclusions that were arrived at. If they didn't, the sentence would read:
"Under such an assumption, they ought to arrive at completely different conclusions."

With the original sentence, they know the conclusions, and they believe that the conclusions should have been (ought to have been) different.

*They - the people making the statement; not the people who ought to have arrived at differernt conclusions.

You've been a lot of help! Thanks!

[ostap77]

You've been a lot of help! Thanks!

Could I use "They were supposed to arrive at completly different conclusions." in the context?