The basic root of our problems and sickness is selfishness, what we can call the inner enemy. Selfishness causes us to engage in negative actions, which place negative imprints on the mindstream. These negative actions can be of body, speech or mind, such as thoughts of jealousy, anger and greed.
Selfish thoughts also increase pride, which results in feelings of jealousy towards those higher than us, superiority towards those lower than us and competitiveness towards equals. These feelings in turn result in an unhappy mind, a mind that is without peace. On the other hand, thoughts and actions directed to the well-being of others bring happiness and peace to the mind.