Michael D'Antonio is the author of the new book "Never Enough: Donald Trump and the Pursuit of Success" (St. Martin's Press). The opinions expressed in this commentary are his.

(CNN) Having long ago committed himself to the proposition that there is no such thing as too much press, Donald Trump may be the most photographed, filmed and quoted man of our time.

Add his own words, offered in books, speeches, Facebook posts and Tweets, and you might conclude that there's little left for this man to share.

But think again. What if all those words were intended, not to reveal, but conceal? What if Trump talks so much because he wants to control the conversation?

Now that Trump is the GOP's presumptive nominee for president, he'll face more intense scrutiny about his many claims to personal success, his political beliefs, his temperament and his character. In each case, the public record is filled with incidents and examples, but a skeptic finds little clarity.

This state of affairs may suffice for anyone buying a steak or an apartment from Trump the salesman, but voters contemplating Trump the candidate for president deserve better answers to the lingering questions.

Here they are:

What is Trump's temperament?

TV audiences have been treated to more than 100 episodes of Trump's reality TV shows "The Apprentice" and "Celebrity Apprentice." The Trump depicted on air is the product of so much editing and consulting by producers and directors that it is no better than a cartoon. More useful is the cumulative Trump record, which includes as many negatives as positives.

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To Trump's credit, he has shown himself to be resilient, coming back from failures that would have sent less confident men and women into business exile. Most notable, of course, is the crisis he experienced in the early 1990s when he was unable to pay personal and corporate debts in the neighborhood of $3.4 billion

Trump is also a nimble entrepreneur, who looks for opportunities and seizes them decisively. Witness his ability to deal in real estate, entertainment and retail merchandising, all at the same time.

On the other side of the ledger, open questions remain about his consistent record of cruelty and excess when dealing with critics and competitors. Trump's code begins with the belief that he's justified in "hitting back ten times harder" whenever he's offended. If our presidents believed in this approach, America would have engaged in shooting wars with untold numbers of countries that have, in recent decades, committed transgressions against the United States.

Would Trump have hit back 10 times harder when North Korea detained the spy ship Pueblo? What about the downing of Malaysia Airlines Flight 17 over the territory of our ally Ukraine. U.S. intelligence indicates a Russia missile likely was responsible. Would Trump have responded by downing 10 Aeroflot planes?

JUST WATCHED Keeping Them Honest: Trump on Afghanistan & gun control Replay More Videos ... MUST WATCH Keeping Them Honest: Trump on Afghanistan & gun control 03:48

We can ask additional questions about Trump's penchant for bullying. In some cases this trait has shown itself in mere words, as he has attempted to humiliate, disparage and marginalize others. In other instances he has sought to force innocent landowners off their properties to make way for his developments. This willingness to use any means necessary to get what he wants raises serious concern about Trump's ability to manage America's affairs in a complex world.

What does Trump believe?

More than any political figure in modern times, Trump represents an ideological puzzle. Although he now claims the conservative Republican mantle, he has often associated himself with liberal and Democratic Party ideas. In 1999 he told CNN, "I've actually been an activist Democrat and Republican."

In the past, Trump said he is "totally pro-choice." Now he is against abortion rights, recently musing about punishing women who might violate a ban on the procedure.

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In the past, Trump was in favor of levying a big tax on the rich , himself included, to pay down the federal deficit. Like banks, rich people have the money, and Trump reasoned that they could afford to help the country out. Today, Trump is in favor of big tax cuts for the wealthy.

In 2000 Trump proposed banning private ownership of assault weapons and increasing the waiting period for the purchase of guns. In the current campaign he has declared himself to be an ardent defender of gun rights, and he has even proposed eliminating gun-free zones near schools.

The list of Trump flip-flops is long and includes his positions on the wars in Iraq and Afghanistan and his regard for Hillary Clinton's performance as secretary of state. Voters, especially those conservatives who want a clear sense of what their standard-bearer will do as president, deserve explanations for these shifts.

How rich is he?

Throughout his life Trump has cited his wealth as evidence of his excellence but without offering verifiable proof of his claims. In the 1970s he cruised Manhattan in a chauffeured limousine and gave others the impression that he was in control of the $200 million fortune amassed by his father.

In the 1980s, when he first made it onto the Forbes magazine list of America's wealthiest men and women, Trump complained often and loudly about how his holdings were underestimated. More recently he said he is worth some $10 billion.

The record produced by those who have looked closely at Trump's finances raises many questions. Writer Wayne Barrett reported in the 1980s that Trump's income as of 1978 was less than $100,000. In the 1993 biography of Trump called "Lost Tycoon," Harry Hurt III noted that during his divorce from his first wife, Ivana, her attorneys found that Trump had never been worth the billions of dollars he claimed. Hurt also reported that in March 1992, Trump's own lawyers said he could not afford to pay Ivana even half of the $20 million he had offered as a settlement.

More recently doubts about his wealth arose in 2005 when journalist Tim O'Brien wrote that Trump was probably worth between $150 million and $250 million. For a man who reveled in his image as a billionaire, O'Brien's estimate was too much to bear. Trump sued. The case was dismissed by the trial judge. Trump appealed. He lost

Were Trump a more circumspect and well-mannered man, who never bragged about how rich he is, his wealth would be less of an issue. However Trump has made his fortune such an important part of his identity that voters deserve to know the truth. Many of the facts are contained in Trump's personal income tax filings, and it is now a campaign tradition for candidates to make these documents public. Clinton has made public all of her returns going back to 2000.

So far, Trump has refused to release his returns because, he says, he is undergoing an audit on returns filed in the last few years. Nothing in the law, or in federal regulations, would prohibit him from making the documents public now, but if he is uncomfortable with releasing those forms, he could simply match Clinton for those years that are settled.

Such a release would reassure the public that Trump is who he says he is -- a really rich man -- and allow a glimpse into other matters, including his charitable giving. It is a matter of conservative orthodoxy that the rich should be spared excessive taxation so they can support society freely with their philanthropy.

Is he a man of character?

Personality, which can be seen in a smile, heard in a glib remark or felt when viewing a performance, is not the most important measure of a man or woman. Many people with winning personalities are, in fact, hucksters, con men, manipulators and deceivers. In fact, the false signals flashed by well-practiced performers, including politicians, compel us to look for the signs of the character beneath the personality.

Experts in assessing character generally look for some traits such as autonomy and life purpose that Trump clearly possesses in abundance. But there are other areas of character , including positive relations with others, ethical behavior, empathy, honesty and humility where Trump would not achieve a very high score.

In his long and very public life, Trump has often shown he is willing to do things others consider wrong in order to get what he wants. This includes using a false identity to make claims about his success, carrying out a bitter divorce dispute in the tabloid press, criticizing the appearance of others and refusing to take the high road when offered the chance.

The most troubling aspect of Trump's character can be seen in his devotion to the so-called birther campaign that sought to delegitimize President Barack Obama. Despite all the evidence to the contrary, birthers led by Trump insisted that some mystery surrounded Obama's status as a citizen born in the United States.

Long after documents were produced to settle this falsely posed question, Trump continued to raise doubts and thus signal his allegiance to those who considered the President to be an unworthy "other." The racism latent in the birther movement was documented in a study by University of Delaware psychologist Eric Heyman, but the link to prejudice was always plain to see. Rather than stand against birtherism, Trump built a following by exploiting it.

In fact, one can find precedent for Trump's birtherism in his previous provocative statements about racially sensitive subjects. Other evidence of his character can be found in his selective use of facts, his tendency to inflame conflict rather than cool it and his devotion to self-promotion.

In the past Trump's character has been well-suited to his pursuit of success as he defines it. But as revealed thus far, it would disqualify him when it comes to the presidency. We can only hope Trump has something better to show and will do it when placed under the pressure of the coming campaign.