I feel very confuse on math logic. For the question above, I don't even know what is the base case. Can anyone give me some hint?
This is the definition of proposition:
- If $P\in Props$, then $P$ is a proposition.
- And if $\varphi$ and $\psi$ are propositions, then the following are all propositions:
- $\neg\varphi$
- $(\varphi\land\psi)$
- $(\varphi\lor\psi)$
- $(\varphi\to\psi)$
- $(\varphi\leftrightarrow\psi)$
- No other string of symbols is a proposition.