Final answer:
Andrew Carnegie planned to retire from business, engage in philanthropy, and limit his personal income to $50,000 a year at age 35, which he later reflected in his philanthropic actions and beliefs about the wealthy's societal responsibilities.
Step-by-step explanation:
In a letter, Andrew Carnegie determined that at age 35 he would do all of the following: retire from business, pursue philanthropic causes, and live on a $50,000 per year income. These actions align with his later life actions and philosophies. Carnegie, via his essay The Gospel of Wealth, advocated for the wealthy to take on the responsibility of distributing their fortunes in ways that would benefit society such as funding hospitals, libraries, and educational institutions. His philanthropy underscored his belief that the affluent had a duty to serve as benefactors to the less fortunate, against the backdrop of American capitalism that enabled his success. Carnegie's legacy as an industrialist who rose from humble origins and later committed to philanthropy set an example for businessmen and shaped his part in American identity.