1. The problem statement, all variables and given/known data Well the problem is: translate the following sentences in first order logic. I cannot verify whether they are correct or not. Maybe someone can point out my mistakes. 1. No barber shaves persons shaving themselves. [tex](\neg \exists x)(Barber(x) \wedge (\forall y)(Shaves(y,y) \Leftrightarrow Shaves(x,y)))[/tex] 2. Any Barber shaves all the persons not shaving themselves. [tex](\forall x)(Barber(x) \wedge (\forall y) (\neg \Shaves(y,y) \Leftrightarrow Shaves(x,y)))[/tex] 3. White birds can fly. [tex](\forall x)(Bird(x) \wedge White(x) \rightarrow Fly(x))[/tex] 4. A bird is happy if all its children can fly. [tex](\forall x,y)(ChildOf(x, y) \wedge Fly(x) \rightarrow Bird(y) \wedge Happy(y))[/tex] Thanks for your help. Please make corrections and suggestions whenever you do see fit. Excuse me for my english.