(CNN) -- Why cheat?
The unfolding saga of doping allegations against Lance Armstrong, the cancer-conquering cyclist who's been stripped of his record seven Tour de France titles, is putting international attention on cheating that hasn't been seen since, perhaps, Tiger Woods.
The alleged cheating in both cases is different. Woods' cheating was marital, resulting in divorce. Armstrong's alleged cheating bears upon athletic performance, putting his reputation and that of the U.S. team on the line.
Sports and marriage aren't the only realms for the cheat. Academia, workplace, science -- they are theaters for the misconduct, too.
Whether on a scale large or small, by someone who's in survival mode or who seemingly has it all, cheating is a frailty shared by all of us, experts in psychology and ethics say.
Have you ever cheated?
It's not a question that an ethicist likes to answer, especially when his nickname is "The Ethics Guy" and he does public speaking for a living.
But Bruce Weinstein, author of "Is It Still Cheating If I Don't Get Caught?" has been confronted with the question in talks before high school students.
"Inevitably, I'm asked whether I cheated," said Weinstein, who received his doctorate in philosophy from Georgetown University. "If I say I never cheated, they say, 'you're lying.' And when I say I did, then they say, 'Why should I listen to you? You're a cheater!'"
Honesty is paramount, Weinstein said.
"When you tell them the truth, they respect you more," Weinstein said. He once cheated in a high school physics class by trying to copy from the valedictorian's lab book, but stopped when the student gave him a "horrible" look, he said.
"I'm not sure I'm going to volunteer it, but if you ask me, I'll tell you," Weinstein said. "Maybe you can learn from my mistake."
CNN's Dr. Wendy Walsh, who holds a doctorate in clinical psychology, admits to cheating, too: When late for an appointment, she blamed traffic.
"Here's the important piece: Even good people cheat," Walsh said. "All human beings lie, even if it's a white lie: Oh, you look great in those jeans!
"But when it is a grave rule violation that is socially, completely looked down upon or there is a legal consequence," Walsh added, "that's where it becomes a little more dicey, when we say, 'Where are the morals and values of the person?'"
In general, why do people cheat?
"There are a couple of ways to answer that question," said Paul Root Wolpe, the director for the Center of Ethics at Emory University.
"On the one hand, people tend to cheat in response to desires and incentives they want. There is individual motivation," Wolpe explained. "And then there are structural pressures, when they feel under pressure for their careers or income."
Atmosphere and institutional culture factor into whether cheating is accepted, said Wolpe.
In sizing up possible influences on cheating, Wolpe asks "is there a strong sense of ethical expectations?" or "is there a wink and a nod that we need to win at all costs?"
"In that case, modeling and mentoring is why people do or don't cheat," Wolpe said.
He contrasted golf with soccer. He described golf as having "a very high expectation of honesty, higher than any sport."
"It's very different in soccer. You often see someone get fouled and throw themselves on the ground. Do you believe he blatantly fouled me as opposed to he barely touched me?" Wolpe asked. "Why is that okay? It's part of the culture of that sport.
"Different cultures tolerate different levels of cheating," he added.
Walsh described cheating as violating a rule you promised to keep, in order to get ahead.
"The payoff for cheating, whether it's cheating on a college SAT test or cheating on your wife or cheating in athletic competition, is you'll win and get all the proceeds and accolades that go with the championship," Walsh said.
In the case of Armstrong, his alleged cheating began "as a little to win, and I don't think he envisioned seven Tours de France and millions of dollars of corporate sponsorship and America's reputation on the line in a worldwide stage," Walsh said.
"The problem with lies like that is that they have to build. They don't go away," she said. "The lies become bigger, bolder, more emphatic."
Why cheat in relationships?
Weinstein cited several reasons, more commonly afflicting long-term marriages or relationships.
"There's the thrill of being with somebody else. There's the thrill of participating in a taboo," Weinstein said. "If things aren't going well in your marriage, an affair may provide for needs that your marriage isn't."
The consequences of cheating in a marriage are considered by some as not as devastating as before, Walsh said.
"One of the reasons we're seeing so much marital infidelity, that version of cheating, is because the consequences have gone down. Divorce is not as expensive as it used to be, and women can support themselves now and there's far less social disgrace associated with it," said Walsh, author of "The 30-Day Love Detox."
But even for people with lots of money such as successful public figures, there can be a high cost elsewhere, such as in Tiger Woods' loss of corporate sponsors and his struggles as a player once his marital cheating was publicized, Weinstein said.
"You have to wonder is if there is a relationship between the scandal and his performance after the scandal," Weinstein said.
What's the answer to cheating?
It starts with leadership and setting standards, Wolpe said.
For example, he was working in Washington this week on a committee revising "Responsible Science," the bible on proper scientific conduct published by the National Academy of Sciences. The guide combats fraud, plagiarism and falsification in research and science, he said.
"Whether an institution or scientific enterprise, the expectation or models that they hold or they actually demonstrate in the way they live their lives are crucial," Wolpe said. "There's really a trickle-down theory in ethics."
The individual must take initiative too, Weinstein added.
"It's very difficult to live an ethically intelligent life," Weinstein said. "Keeping your word, keeping things private, telling the truth, avoiding hurting people, being fair and compassionate, all this takes work."