This is a quote from the book "The Virtue Of Selfishness" by Ayn Rand
... all philosophers, Aristotle, did not regard ethics as an exact science; he based his ethical system on observations of what the noble and wise men of his time chose to do, leaving unanswered th
e questions of: why they chose to do it and why he evaluated them as noble and wise.
read full book
Most philosophers took the existence of ethics for granted, as the given, as a historical fact,
and were not concerned with discovering its metaphysical cause or objective validation. Many of them attempted to break the traditional monopoly of mysticism in the field of ethics and, alleged...