We are only asked to symbolize this argument, but we may as well prove it here. The layering looks daunting.
The father of the father of Annnette flies. Anyone who has a father who flies fears loss. So, the father of Annette fears loss.
Let Fxy - x is a father of y, a - Annette, Vx - x flies, Lx - x fears loss.
- (∃x){Fxa • (z)(Fza ⊃z = x) • (∃y)[Fyx • (w)(Fwx ⊃w = y) • Vy]}
- (x)[( ∃y)(Fyx • Vy) ⊃Lx]
- ∴(∃x)[Fxa • (y)(Fya ⊃y = x) • Lx]
- Fma • (z)(Fza ⊃z = m) • (∃y)[Fym • (w)(Fwm ⊃w = y) • Vy] ......... 1 EI x/m
- (∃y)(Fym • Vy) ⊃Lm ......... 2 UI x/m
- (∃y)[Fym • (w)(Fwm ⊃w = y) • Vy] ......... 4 Simp.
- Frm • (w)(Fwm ⊃w = r) • Vr ......... 6 EI y/r
- Frm • Vr ......... 7 Simp.
- (∃y)(Fym • Vy) ......... 8 EG
- Lm ......... 9,5 MP
- (z)(Fza ⊃z = m) ......... 4 Simp.
- Fya ⊃y = m ........ 11 UI z/y
- (y)(Fya ⊃y = m) ......... 12 UG
- Fma ......... 4 Simp.
- Fma • (y)(Fya ⊃y = m) • Lm ......... 14,10,13 Conj.
- (∃x)[Fxa • (y)(Fya ⊃y = x) • Lx] ......... 15 EG
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