Dirt is related to Seed. Seed is related to Stone. Stone is related to Weed. 
Planet is related to World. World is related to Place. Place is related to Point. 
Dirt <--RelatedTo--> Seed <--RelatedTo--> Stone <--RelatedTo--> Weed 
Planet <--RelatedTo--> World <--RelatedTo--> Place <--RelatedTo--> Point 