The question: 'Why Should I Be Good' is a badly worded question, because it cancels the very meaning of the questioner. The question as it stands, is answered categorically when it is said that I should be good and do good because it is good to do good. When some action or state of mind is good, it is its very reason for realising it. When something or some state of mind is evil that is the very ground for abstaining from it.
However, this answer does not satisfy the questioner. When an answer does not satisfy the questioner, it means that the question is not understood either by the questioner or by the person who replies or by both. In such a case it is always fruitful to undertake the analysis of the question again. Let us follow our own advice in this case.
Tradition accepts certain values as highly important. Truth, honesty, chastity, purity and selflessness are regarded as good. Society throughout the world, has impressed these values through drama and dance, songs and stories, parables and sermons. Men and women who have shown these qualities in extraordinary excellence have been eulogised in the imperishable language of the poets and dramatists. Again, characters have been created by the poets, novelists and dramatists who bring out the beauty of such virtues. Moral prophets have risen to create prestige for these values. So great is the influence of the poets and the prophets that human society in spite of their defiance of these values, pays lip service to them and even cannot withhold its homage to those who martyr themselves for these values.
These values of truth, honesty, chastity, selflessness claim our allegiance and obedience. Our biological impulses do not feel attraction for them. On the contrary, they impel us to revolt against them in open and covered ways. If we see the question in this context, we can correctly analyse its meaning. This question does not mean what it pretends to be. When properly analysed in this context, it means 'why should I be truthful, chaste, honest and selfless?'
'Why Should I Be Good - Historical Perspective' by S.P. Kanal