##  [Second-Order Logic](/second-order-logic) 

  ##  [Second-Order Logic](https://mathlogic.quantumdictionary.io/second-order-logic-0) 

  

 [![Mathematics & Logic Dictionary](/sites/default/files/styles/large/public/2026-01/Mathematics%20%26%20Logic.png.webp?itok=UhtTRPnp)](/topic-specific-dictionaries/natural-formal-sciences/mathematics-logic)

- Natural & Formal Sciences -

**Mathematics & Logic Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A logical framework extending first-order syntax by allowing quantification not only over individual elements of a domain but also over relations, functions, or subsets of the domain (i.e., second-order variables range over predicate-like objects).