This is a quote from the book "The ​Virtue Of Selfishness" by Ayn Rand
...ation, particularly when it involves the moral character of another person. When one pronounces moral judgment, whether in praise or in blame, one must be prepared to answer “Why?” and to pr ove one’s case — to oneself and to any rational inquirer.

The policy of always pronouncing moral judgment does not mean that one must regard oneself as a missionary charged wit
h the responsibility of “saving everyone’s soul” — nor that one must give unsolicited moral appraisals to all those one meets. It means: (a) that one must know clearly, in full, verbally...
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