I saw some sentences using this phrase "for all I know" but wasn't quite sure what is its exact definition and also whether a modal verb such as "could, may or might" expressing uncertainty must be present in the sentence.
The following are some possible definitions:
- According to the information I have; I think; probably. (usually implies uncertainty)
- Based on what I know (usually expressing displeasure)
- As far as I know (used to show indifference)
- I really don't know (used to show complete ignorance)
And these are statements containing the phrase:
- For all I know, the mayor has resigned already.
- She may have gone to town for all I know.
- He wears a ring, but he may be single, for all I know.
- For all I know, there may be someone with you now.
- The man I met on the beach yesterday seemed friendly, but he could be a thief, for all I know.
- For all I know, the girl was buried alive in the Arabian sands.
- They've decided to hire Jack for all I know.
What does the phrase "for all I know" mean exactly?