When you walk past an empty cup on the street, do you toss a quarter into it? Would it change your mind if the person holding was a well-known actor in Hollywood?

Golden Globe winner Richard Gere went undercover as a homeless person while in New York, filming Time Out Of Mind. The film is about a homeless man, played by Gere, who is attempting to reconcile the relationship he has with his estranged daughter.

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A photo posted on a Gere community Facebook page addressed the plight of homelessness. Editor's Note: We can't confirm that this is a direct quote from Gere himself.

Richard Gere's Facebook page - facebook.com

Richard Gere's Facebook page - facebook.com

Gere addressed his experience shooting Time Out of Mind in an interview with the Associated Press. The actor, who the AP reports has worked with the National Coalition for the Homeless, was moved by the reactions of passersby as he stood on the street corner:

Getting to actually experience the feeling of begging, if only for hours at a time, Gere says, was more like being a black hole than being invisible. He could feel people avoiding him, going through an "interior opera" of guilt -- which, he notes, ultimately "has very little to do with the reality of that guy on the street corner."

He says the experience gave him a taste of "how quickly we (can) deteriorate mentally" in a situation like that.

The issue of homelessness is widespread, affecting an estimated billion people worldwide. That number may be higher or lower, but a global housing survey hasn’t been conducted since 2005, when the United Nations (UN) collected data on how many people lacked adequate housing and shelter worldwide.

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What does homelessness in America look like?

In the United States, the 2014 Annual Homeless Assessment Report (AHAR) to Congress reported that at the time of the investigation, 578,424 people were homeless on any given night in America. There were also high instances of homelessness amongst populations such as veterans, but homelessness can effect a range of different people. This includes veterans, men and women, and even children.

According to AHAR, 23 percent of the homeless individuals surveyed were under the age of 18. Of those children, 6,274 were unaccompanied.

As Attn: has covered previously, there are many factors that can cause homelessness, including growing economic inequality, a lack of affordable housing, gentrification, and mental illness, among other variables. Many cities also treat homelessness as a criminal problem. 

It’s an ongoing, complex systemic issue that needs to be talked about, as it affects all of society, not just a subset of people.

How can homelessness be addressed?

The United States Interagency Council on Homelessness says that preventative measures that keep people from becoming homeless are very effective in tackling the issue of homelessness. They also drafted a plan in 2010 called Opening Doors: Federal Strategic Plan to Prevent and End Homelessness. 

The plan focuses on increased leadership and civic engagement. It also promotes increased access to stable, affordable housing and economic security. In addition, it promotes the health and stability of the American people, including a focus on youth aging out of foster care, as well as an increased focus on the importance of behavioral health care. Finally, the plan looks to transform homeless crisis response systems in cities across America. 

Editor's Note: A previous version of this article included that this photo appeared on Gere's Facebook page. This is incorrect. The photo originally appeared on a Richard Gere Facebook community page.