Psychology is related to Reading. Bed can be used for Reading. you are likely to find Bag in/at/on Bed. Bag is related to Sock. 
Ease is a different concept from Hard. Hard is related to Quiet. Quiet is related to Whisper. 
Psychology <--RelatedTo--> Reading <--UsedFor-- Bed <--AtLocation-- Bag <--RelatedTo--> Sock 
Ease <--DistinctFrom--> Hard <--RelatedTo--> Quiet <--RelatedTo--> Whisper 