Distinguishing Good and Evil
To determine whether an action is good or evil, right or wrong, Buddhist ethics takes into account three components involved in a karmic action. The first is the intention that motivates the action, the second is the effect the doer experiences consequent to the action, and the third is the effect that others experience as a result of that action. If the intention is good, rooted in positive mental qualities such as love, compassion, and wisdom, if the result to the doer is wholesome (for instance, it helps him or her to become more compassionate and unselfish), and if those to whom the action is directed also experience a positive result thereof, then that action is good, wholesome, or skillful (kusala). If, on the other hand, the action is rooted in negative mental qualities such as hatred and selfishness, if the outcome experienced by the doer is negative and unpleasant, and if the recipients of the action also experience undesirable effects from the action or become more hateful and selfish, then that action is unwholesome or unskillful (akusala).
It is quite probable that on the empirical level an action may appear to be a mixture of good and bad elements, in spite of the intention and the way it is performed. Thus, an action committed with the best of intentions may not bring the desired result for either the doer or the recipient. Sometimes an action based on negative intentions may produce seemingly positive results (as stealing can produce wealth). Due to lack of knowledge and understanding, people may confuse one set of actions with an unrelated set of results and make wrong conclusions, or simply misjudge them on account of social values and conventions. This can lead to misconceptions about the law of karma and loss of moral consciousness. This is why precepts are necessary in the practice of moral discipline: they provide definite guidelines and help to avoid some of the confusion that empirical observation and social conventions may entail.
Buddhist moral precepts are based on the Dharma, and they reflect such eternal values as compassion, respect, self-restraint, honesty, and wisdom. These are values that are cherished by all civilizations, and their significance is universally recognized. Moral precepts that are based on such values or directed toward their realization will always be relevant to human society, no matter to what extent it has developed. Moreover, their validity can be empirically tested on the basis of one's own sensitivity and conscience, which are beyond factors of time and place. Killing, for instance, is objectionable when considered from the perspective of oneself being the victim of the action (although when other lives are subjected to the same act, its undesirability may not be felt as strongly). The same is true with regard to stealing, lying, and sexual misconduct. Because Buddhist moral precepts are grounded on these factors, their practicality remains intact even today, and their usefulness is beyond question.