Four mental engagements 四作意

The nine ways of resting the mind, or stages of shamatha practice can be condensed into four mental engagements (Tib. ཡིད་ལ་བྱེད་པ་བཞི་, yi la jepa shyi; Wyl. yid la byed pa bzhi):

瑜伽三十卷十一頁云：即於如是九種心住，當知復有四種作意。一、力勵運轉作意。二、有間缺運轉作意。三、無間缺運轉作意。四、無功用運轉作意。於內住、等住中，有力勵運轉作意。於安住、近住、調順、寂靜、最極寂靜中，有有間缺運轉作意。於專注一趣中，有無間缺運轉作意。於等持中，有無功用運轉作意。當知如是四種作意，於九種心住中，是奢摩他品。

1. tightly focused engagement (Tib. བསྒྲིམས་ཏེ་འཇུག་པའི་ཡིད་བྱེད་, drim té jukpé yi jé) – relates to the first two stages of resting the mind
2. interrupted engagement (Tib. ཆད་ཅིང་འཇུག་པའི་ཡིད་བྱེད་, ché ching jukpé yi jé) – this occurs from stage three to stage seven, when one is still susceptible to the obstacles of dullness and agitation and is therefore unable to abide for a long time
3. uninterrupted engagement (Tib. ཆད་པར་མེད་པར་འཇུག་པའི་ཡིད་བྱེད་, chepar mepar jukpé yi jé – at stage eight one is able to remain unaffected by the obstacles of dullness and agitation without too much exertion
4. effortless engagement (Tib. རྩོལ་བ་མེད་པར་འཇུག་པའི་ཡིད་བྱེད་, tsolwa mepar jukpé yi jé) – at the ninth stage one is able to maintain the practice effortlessly