“One may not be skilled in the habit of other‘s thoughts but at least one can make this resolve: “I will be skilled in the habit of my own thoughts.” This is how you should train yourself, and this is how it is done. A woman, a man or a youth fond of seIf-adornment, examining his refiection in a bright, clear mirror or a bowl of clear water might see a blemish or pimple and try to remove it. And when he no longer sees it there, he is pleased and satisfied and thinks: “It is an advantage to be clean.”
In the same way, one’s introspection is most fruitful in good states when one thinks: “Am I usually greedy or hateful, overcome by sloth and torpor, with excited mind or filled with doubt or anger or am I not? Do I usually live with soiled thoughts, or clean thoughts? With body passionate or not, sluggish or fuli of energy, uncontrolled or well controlled?”
If on seIf-examination one finds that he does live with these evil unprofitable states, then he must put forth extra desire, effort, endeavour, exertion, energy, awareness and attention to abandon them.
And if on self-examination he finds tha he does not live with the evil unprofitab states, he should make an effort to establish those profitable states and further destroy the defilements.”
Anguttara Nikaya v.91