Calvin (really loud): Mom, can I set fire to my bed mattress?

Mom: No, Calvin.

Calvin: Can I ride my tricycle on the roof?

Mom: No, Calvin.

Calvin (not so loud): Then can I have a cookie?

Mom: No, Calvin.

Calvin (thinking to himself): She’s on to me.

The second-most important character in the wonderful old comic strip “Calvin and Hobbes” was engaging in a classic negotiating technique, one that sometimes even works.

You ask for something totally unreasonable, just to set a high bar. Then you walk it back, and back, and back some more, until you are asking for something that seems not only normal but, by comparison, hardly anything. And you get it.

Or not.

Sometimes, as happened with Calvin and his mom, the wishing well has been poisoned — and she is so used to saying, “No, Calvin” — so even a reasonable request gets rejected.

A few weeks ago, a conference of folks who are really, really worried about the impact that pornography can have on people, especially children, assembled for a well-meaning confab here in Salt Lake City. They doubtless had some real issues to discuss and some valid worries about how easy it is for even young children to see some really gross stuff online.

But, in the minds of most reasonable people, one of the speakers totally undercut any good things that were said that day by counting as a blow for decency her successful efforts to get the Costa Vida restaurant chain to take down pictures of a bikini-clad woman on a surfboard.

Costa Vida’s whole schtick is tropics, sunshine, fun on the beach. Its logo is a big blue breaking wave. Which quite logically leads to images of surfboards, a great many of which, in the real, non-porn world, are steered ashore by strong, healthy women in brief two-piece bathing suits.

People who are afraid of that are afraid of life.

And their efforts to convince parents, schools and governments to do something about the real (if vastly overstated) harms of geniune pornography are likely to be discounted by people who might otherwise have sympathy for their cause.

It’s the same kind of thing when folks crusade against the placement of Cosmopolitan magazine at retail check-out counters on the grounds that, according the the billboards, “Cosmopolitan Magazine Contains Porn.”

Well, kind of. The magazine is mostly about sex. But, because it is aimed at a female audience, Cosmo seeks to be spicy mostly in words rather than pictures. Which means that it won’t reach 98 percent of males, and its potential to actually damage anyone is small.

A much more hazardous message was laid down last week at the General Conference of The Church of Jesus Christ of Latter-day Saints.

In what was seen as an official LDS nod to the rising #MeToo movement, apostle Quentin L. Cook said it was a good thing that more people were speaking out against what he called, “nonconsensual immorality,” apparently a rather squeamish term for sexual harassment, abuse and rape.

So, for a moment, he rightly placed the church on the side of victims who, increasingly, have the courage to speak out against such behavior. It is, he said, “against the laws of God and society.”

And then he had to go and spoil it all by adding, “However, those who understand God’s plan must also oppose consensual immorality, which is also a sin.”

Cook was rightly lambasted by advocates for the victims of sexual assault for describing it as mere “immorality,” for seeming to equate stuff that everyone at least claims to be against — assault — with behavior that does not and should not be in the same category — normal sexual relations.

Oh, the official church line is that victims are victims, not perpetrators, not sinners, and do not need to repent. But Cook’s clumsy formulation recalls the kind of lesson that Elizabeth Smart, still a loyal and true Mormon, has been trying for years to remove from the lexicon.

That’s the idea that anyone who has engaged in sexual contact — even if it was rape — is somehow damaged goods or, in the utterly heartless metaphor Smart remembers hearing, “chewed gum.”

Women who take that message to heart are the ones who are more likely to be the victims of sexual assault, to be too frightened or ashamed to report it. Men who hear it are the ones who will take advantage of those women and then count on those very fears to get away with it. Again and again.

There are good and bad aspects of sex, sexuality and plain old sexiness. Those who can’t tell the difference aren’t helping anyone. Except the perpetrators of abuse.

George Pyle, The Tribune’s editorial page editor, thinks he has reached an age where he can appreciate great beauty without making a fool of himself. gpyle@sltrib.com