Editorís note: Paul Tash, the chairman and CEO of the Tampa Bay Times, graduated from Indiana University in 1976. He was the speaker Saturday at the undergraduate commencement, where he delivered these remarks.Hello, fellow Hoosiers. It is great to be back home again in Indiana.To President McRobbie and the facultyÖTo all the proud familiesÖAnd especially to the graduates ÖThank you for letting me share this celebration with you. Forty-two years ago, I was in your place, getting my bachelorís degree. I wish my mom and dad could be here again today. Maybe they are.And 100 years ago this spring, the speaker at Indianaís commencement was Theodore Roosevelt, the former president. According to press accounts, there were 8,000 people in the crowd but only 236 graduates, because many students were in Europe fighting World War I.Feeling the weight of that centennial precedent and the responsibility of todayís assignment, I asked around for some advice. Hereís the best: "Being a college commencement speaker is like being the guest of honor at an Irish wake: They canít have the party without you, but youíre not expected to say very much."Iíll try to follow that good counsel.My turn at the podium today honors the proud tradition of journalism at Indiana University, and it recognizes journalism as an essential foundation of a healthy democracy.While you were students here, the university installed a statue of Ernie Pyle, the World War II correspondent who was killed in combat. That statue sits outside the Media School and Franklin Hall. Its placement there illustrates the higher purpose of journalism: to serve the greater public good. Ernie Pyle belongs to all of us. He wrote for everybody.Over the course of my career, Iíve had the privilege of editing, sponsoring or recognizing journalism at the highest professional standards. During my nine years on the board of the Pulitzer Prizes, I would marvel at the work that came before us, whether or not it won a prize. And I would leave those meetings struck by all the things the world simply would not know ó except for the work of journalists.There is a vivid example just up the road at the Indianapolis Star. Reporters there uncovered the scandal that USA Gymnastics wanted to keep quiet. By pursuing their leads to a courthouse in Georgia, those reporters broke the story that Olympics team doctor Larry Nassar was molesting dozens of athletes, even while people who could have stopped him turned a blind eye. Their story was an opening salvo in what would become the #MeToo movement.Except for those reporters, who knows how much longer that doctor might have escaped punishment, or how many more young women might have become his victims in the meantime?Compare that work to another story that was getting wide circulation about the same time.As that story goes, a pizza parlor in Washington was the home base for a child sex trafficking ring that included Hillary Clinton. What started with a tweet by a white supremacist picked up steam on Facebook and Reddit, and before long a significant segment of the population was convinced that a candidate for president of the United States was running a child prostitution ring out of a pizza restaurant a few blocks from the White House.One man from North Carolina got so worked up that he showed up to investigate at Comet Ping Pong on a Sunday afternoon and started shooting inside the restaurant.Even after he was sentenced to prison, even after the so-called scandal was widely discredited, some people refused to give up on it. There was a demonstration in Lafayette Park, just across from the White House, demanding action to investigate Pizzagate and bring the criminals to justice.Two stories. One built on facts. The other a complete fraud. Both sent someone to prison. In the story from the Indianapolis Star, it was the doctor who was exposed by the reporters. In the story about Pizzagate, it was somebody who believed the fraud and acted upon it.Itís tempting to dismiss the man who shot up the pizza parlor as a flake and the story that provoked him as outlandish Öexcept that there is such a thing as fake news, and we discount its influence at our peril.Another name for fake news is propaganda, and those who crave power will use it to move hearts and minds.Earlier this year, an American grand jury indicted three Russian organizations and 13 individuals for trying to meddle in our last presidential election. According to the indictment, the Russians stole the identity of real American citizens, set up phony bank accounts, organized political rallies and posted false stories on social media sites, all with the stated goal of "spreading distrust toward the candidates and the political system in general."One Russian tycoon who was indicted shrugged off the charges and had this to say: "The Americans are very impressionable people. They see what they want to see."Which reminds me of what P.T. Barnum said about people who came to the circus: "The bigger the hokum, the better people will like it."Journalism tries to dispel the hokum, to set the record straight, to help us see what is true. My colleagues at the Tampa Bay Times started PolitiFact to separate truth from fiction. PolitiFact rates statements on the Truth-O-Meter, from "True" all the way to "Pants on Fire."These days, itís hard for PolitiFact and similar efforts to keep up. There are so many actors, so many platforms, and so many ways for a story to find an audience, whether itís true or not. And truth be told, our efforts are a little like antibiotics, after the germs of falsehood have already been carried by political discourse into the bloodstream of the Body Politic.What we also need is a stronger immune system, so that democracy is more resistant to those who would manipulate perceptions to advance their selfish purposes.For the last four years (plus or minus), your education here at a great public university has been part of building that stronger immune system. Indiana University has helped prepare you not just as professionals, but also as citizens, as guardians of individual liberty and collective self-government. For that vital exercise, you should carry forward some values you have employed in your academic pursuits.One of those values is curiosity. There is an awful lot about the world we donít know, and some things we think we know may turn out not to be true, after all.So I also encourage you to borrow one of journalismís core values: skepticism. That principle from my work is to take nothing ó nothing ó at face value. The advice to new reporters goes like this: "If your mother says she loves you, check it out."We are besieged, these days, with information, bombarded from all directions with stories from all kinds of sources. Many stories come from journalists, people who are trying to get the facts straight. Journalism is a human endeavor, so their work will be imperfect. But the purpose is noble. And tomorrow provides another chance to get even closer to the truth.Other stories come from those who use lies to play upon prejudice and exploit fear. Their agenda is to subvert truth and advance their own influence. Fact or fake? Democracy depends on our ability to tell the difference. Journalism can help. It can be a great civic asset. But the final responsibility rests with us as Americans. And so, my fellow Hoosiers, keep your guard up. Remember that advice to new reporters: "If your mother says she loves you, check it out."Except for today. Probably every day, but today, of all days, when your mother says she loves you, I am absolutely, completely, 100 percent certain that she means it.May good fortune smile on all your endeavors, and thanks again for letting me share this proud day with you. I will remember your graduation from Indiana University as fondly as I do my own.