Slaves of the world
When the heart is subdued by the world, meaning when a person is obedient towards the world, wherever that person sees ways of obtaining world's enjoyments, will follow those ways. This means whatever his/her inner desires are, he/she will follow those and make that person to become obedient to his/her inner desires. Imam Ali (A.S) said: This type of person is someone who if sees a thing which his/her heart likes and is in others hands, will be humble towards them and will become totally obedient towards them in order to get to that thing \.
 Rasa'el Bandegy (Farsi Edition) by Ayatollah Mojtaba Tehrani, page 105.