# Assignment I

Basic exercises that give students hunches how informal languages, for instance daily use of English, can be translated to the formal language in first order logic, and vice versa.

Common Mistakes:

• In X2003 (a), some students interpret ‘Jack only likes dogs’ as ‘Jack likes all the dogs’ or ‘Jack dislikes all people and Jack likes at least one dog’ etc. However, the best way to interpret is to say ‘Anything that Jack likes must be a dog’.
• Many students have problem understanding the difference between $\wedge$ and $\supset$, especially within the scope of quantifiers. Usually, when translating daily use sentences, within the scope of every existential quantifier, one may see conjunctions, meanwhile, within universal quantifiers, implications. This is not necessarily true, but it holds most of time.