I have to translate the following English sentences into First-Order Logic without using quantifiers:
1. Everyone on flight 815 has a story. 2. No one knows what is inside the hatch. 3. Someone on the island isn’t on the flight manifest.
I have tried it, but can't translate without using ∀ and ∃:
1. ∀x fight815(x) → story(x) 2. ∀x ⌐(knows(x) → inside hatch(x)) // not sure about this OR ¬ ∃x Knows(x, inside hatch) 3. ∃x island(x) Λ ⌐(flight manifest(x))
Is it possible to do it. If not, why?
Refer chapter 8 of Artificial Intelligence: A Modern Approach (3rd edition). Stuart Russell and Peter Norvig, Prentice Hall (2010)