Carlos Slim has a $60 billion fortune and is the fifth richest person in the world - here are 18 of his most brilliant quotes

"Success is not about doing things well or even very well, or being acknowledged by others."

He continued: "It is not an external opinion, but rather an internal status. It is the harmony between the soul and your emotions, which requires love, family, friendship, authenticity and integrity."

Source: Letter to Young People, a 1994 address to the university community in Mexico City

"Firm and patient optimism always yields its rewards."

This is one of Slim's guiding principles at his Grupo Carso business.

Source: CarlosSlim.com

"If you are in business, you are not enjoying. You are working."

This was his response when asked if he would consider buying the New York Yankees, of which he is a fan.

Source: Newsweek

"Shorter workweeks are a solution to civilization shifts."

Source: Bloomberg Businessweek

"When you give, do not expect to receive."

Source: Letter to Young People, a 1994 address to the university community in Mexico City

"This is the most surprising example of national unity that I've had the pleasure of seeing in my life."

Slim stated this during a 2017 press conference in Mexico City, referring to how President Donald Trump's attacks on his country — particularly on trade and immigration topics — helped unite Mexicans.

Source: Reuters

"Twitter is not a way to negotiate."

Slim was referencing Trump's penchant for discussing foreign relations policy via the social media platform.

Source: CNN

"Do not allow negative feelings and emotions to control your mind."

"Emotional harm does not come from others," he explained. "It is conceived and developed within ourselves."

Source: Letter to Young People, a 1994 address to the university community in Mexico City

"I believe that we have to find means for all desirable things to be universally accessible."

He listed those as: "Culture. Entertainment. Sport. Communication. Health. Food. Housing. The fundamental things."

Source: The Telegraph

"All times are good times for those who know how to work and have the means to do so."

Another of Slim's Grupo Carso guiding principles.

Source: CarlosSlim.com

"Life's road is very long, but it is traveled fast."

"Live the present intensely and fully, do not let the past be a burden, and let the future be an incentive," he continued. "Each person forges his or her own destiny and it may influence reality. Do not ignore it."

Source: Letter to Young People, a 1994 address to the university community in Mexico City

"There's resistance to all change. The most profound change is this new civilization. This new civilization changes from an industrial society to a service one."

Source: Bloomberg Businessweek

"Work well done is not only a responsibility to yourselves and society; it is also an emotional need."

Source: Letter to Young People, a 1994 address to the university community in Mexico City

"It's important that people don't retire at 50, 60, or 65 years old. I think people should retire later, because they'll have more knowledge and experience. And I think they should work three days a week, so that it creates space for others."

Source: Bloomberg Businessweek

"Guilt and fear make the present difficult and obstruct the future. To fight them, let us have good sense and accept ourselves as we are, with our realities, our merits, and our sorrows."

Source: Letter to Young People, a 1994 address to the university community in Mexico City

"It's important to give a better country to your children, but it is more important to give better children to your country."

Slim said this to Diane Sawyer during a "Good Morning America" segment.

Source: KVIA.com

"There is no challenge that we cannot overcome by working united, and with clear vision in the goals and knowing the tools.’

Source: CarlosSlim.com

"At the end we depart with nothing. We leave behind only our work, family, and friends, and, perhaps, a positive influence which we have planted."

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