Policeman is related to Uniform. Uniform is related to Military. 
Servant is a different concept from Slave. Slave is a different concept from Independent. Independent is related to Revolutionary. 
Policeman <--RelatedTo--> Uniform <--RelatedTo--> Military 
Servant <--DistinctFrom--> Slave <--DistinctFrom--> Independent <--RelatedTo--> Revolutionary 