First Order Logic

First Order Logic (FOL) overcomes the limitations of Propositional Logic

Also called as 

• Quantificational Logic
• Predicate Logic
• First-Order Predicate Logic

It contains variables that refer to things in world and we can quantify over them.

First Order Logic is 

- declarative like Propositional Logic

- expressive like Natural Language

Sentences are viewed as expressing relations between individuals.

SYNTAX / COMPONENTS

1. Terms : logical expression representing objects or individuals
   a. Constants : they depict properties. Example: Blue, Binod
   b. Variables : they depicts objects. Example: `x`
   c. Functions : they depict relations. Example: friendOf(Shweta)
   
   
2. Predicates: these are propositions containing variables. These take argument as Terms. 
   - If one argument is there, they are called property
   - If two arguments are there, they are called relation
   Example
   a. friends(Pandit, Shweta) [depict relation | arguments are constant Terms]
   b. isPink(Jeans(Sonam)) [depict property | Sonam's jeans is Pink]
   
   
3. Connectives: `\neg,\vee,\wedge,\implies,\iff`
   
   
4.