##  [Indiscernible Set](/indiscernible-set) 

  ##  [Indiscernible Set](https://mathlogic.quantumdictionary.io/indiscernible-set-0) 

  

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**Mathematics & Logic Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A subset or sequence of a structure whose finite tuples have the same type over a fixed parameter set whenever the tuples have the same order-type inside the subset; equivalently, no formula with parameters from the base distinguishes between tuples that are order‑equivalent. Indiscernibles serve as highly symmetric configurations used in combinatorial and classification arguments.