a1p3

[Saurabh Joshi]

Anyone have tips on how to start this? I was thinking on doing induction
(prove it if the Theta only substitutes 1 atomic symbol, then show that
it can substitute n+1 atomic symbols).

[Justin Harris]

Post by Saurabh Joshi
Anyone have tips on how to start this? I was thinking on doing induction
(prove it if the Theta only substitutes 1 atomic symbol, then show that
it can substitute n+1 atomic symbols).

I think there is a very nice way to do it by contradiction.

Induction seems good but the way you proposed it might not be the best
way. However you should still note that if the substution substitutes 1
atomic symbol, then it can substitute n+1 atomic symbols.

I think he gave us a hint about using truth tables. I used a truth
table and added a few cunning notes.

[Chris Tidder]

Post by Saurabh Joshi
Anyone have tips on how to start this? I was thinking on doing induction
(prove it if the Theta only substitutes 1 atomic symbol, then show that
it can substitute n+1 atomic symbols).

Are the formulas that are substituted for the atomic symbols in Phi
guaranteed to be valid formulas?