I teach my high school English students about logical fallacies, as good writers and readers need to know both how to avoid engaging in logical fallacies and how to spot them when they occur in wild.

For today's lesson, we will talk here about the "No True Scotsman" fallacy. It's a form of post-hoc reasoning or special pleading that tries removing an unwelcome or unsuccessful in-group member to an out-group.

It was first identified in 1971 by British philosopher Anthony Flew, who tells us to imagine a Scotsman reading the newspaper and seeing a story about a terrible crime committed by an Englishman. "Of course," our Scotsman thinks, "no Scotsman would do that!" The next day's paper reveals an even worse crime committed by a Scotsman. Our imaginary Scotsman now must revise his thinking: "No true Scotsman would do that!" he now says.

Had Flew been an American watching our politics, he might have named the fallacy "No True Republican," given that every election cycle in which Republicans lose ground, the GOP insists the problem is that its candidates are impurely conservative.

It's what they said about Mitt Romney and John McCain, the two who lost elections to President Barack Obama. They even said it about George W. Bush as Democrats were about to sweep Congressional elections in 2006.

Heck, it's an article of faith among many Republicans today that even Bob Dole was not conservative enough. Bob Dole!

And now that it seems almost certain that Donald Trump will lose next month, there is a wicked scramble afoot among elected and campaigning Republicans to say their current presidential nominee isn't a Scotsman – er, Republican.

The problem for Republicans is that all of those men, and all the men who have been elected to or nominated for the presidency under the GOP banner in living memory, are the Republican Party, and the party is Trump.

Trump is a straight white male Baby Boomer born into privilege. He holds implicitly racist, sexist and elitist views about fellow Americans; he holds explicitly nativist and jingoistic views about non-Americans. His primary policy goals seem to be protecting the wealth of the richest Americans and stemming the demographic tide steadily pushing white men into minority status in this country.

Overwhelmingly, Republicans in this country are demographically like Trump. They are white, older and skew socially conservative (at least when they are described by their religiosity) and nativist. They are also more likely to be men than women at any age, of any race and with any level of education.

And, at least in the initial post-"Trump tape" polling, they still overwhelmingly support the nominee. Self-described conservatives and Republicans are just as suuportive of Trump now as they were during the primaries. It seems impossible to believe, but Trump, whose national polling numbers hover around 40 percent currently, won more GOP primary votes than anyone in history this year.

There are minor differences between Trump and past Republican candidates, sure. For example, McCain is from a military family and is himself a war hero, while Trump, son of a wealthy New York real estate mogul, was able to score repeated medical deferments from the Vietnam draft. Romney lacks Trump's questionable history with women and even, for a time, valued their right to choose an abortion.

The entire field of primary candidates for this year's cycle looked a lot like Trump. Some were less old (Wisconsin's own Scott Walker, for example), less white (Ben Carson), less bombastic (John Kasich) or less male (Carly Fiorina), but to a one, they all subscribed to an ideology that privileged white, male, wealthy Americans at the expense of non-white poor Americans and immigrants.

Basically, the only thing that separates Trump from the rest is his lack of a filter and – critically – years spent being recorded running his unfiltered mouth.

This is no small thing. After Trump loses, his insufficient conservatism means that in 2020 Republicans will no doubt nominate someone who is at least as conservative, if not moreso, than Trump in an attempt to appeal to an imaginary conservative majority in this country.

A number of commentators and voters took Indiana Governor Mike Pence's debate performance a week ago to be a sign that he is eyeing a run against President Hillary Clinton in four years. But beyond being literally on the ticket with the man, there is nothing about Pence's record in Congress or as a governor to suggest that he is different from Trump or appeals to a different pool of potential voters.

Pence's policies jailed a woman for having a miscarriage and created an HIV outbreak in his state. Pence supports all the usual conservative economic mumbo-jumbo but has not miraculously turned his state into a supply-side paradise.

History suggests Pence is doomed in 2020; no failed vice-presidential candidate has won a party's nomination since Walter Mondale in 1984 – and Mondale had been on a winning ticket in 1976.

Other possible 2020 contenders include Walker, whose Wisconsin GOP seeks policies dedicated to restricting the rights of women and economically benefitting the wealthy. I mean, the latest WisGOP proposal for education policy – my wheelhouse – is the so-called "education savings account," a giveaway to wealthy parents. It's hard for poor parents to divert part of any paycheck into such an account, even if it has tax benefits, when every cent of their paycheck is needed to buy basic necessities like food and shelter.

Then there's Ted Cruz, who makes Scott Walker look like Ted Kennedy.

On issue after issue, Republicans likely to run in the next presidential election support policies that favor the wealthy, the white and the male. Voter ID, for example, has been in the news here in Wisconsin lately. Those most likely to lack adequate voter ID, it is well documented, are non-white young people, Republicans' worst constituency. Even among the old, where Republicans do well, older whites (who vote Republican) are much more likely to have access to documents necessary to get a proper state ID for voting than older non-whites (who don't).

Coincidentally, the state that brought us the U.S. Supreme Court decision allowing for strict ID laws is Indiana, the state that also brought us Mike Pence. Maybe that's not really a coincidence after all.

Republican voters are a shrinking demographic group. There are more Americans under 35 than over 55. By 2020, the youngest voters will have been born post-9/11, most voters will have been born post-Watergate and two-thirds of voters will be too young to have been able to vote for Reagan. Those voters are overwhelmingly not white men and unlikely to be or lean Republican or conservative.

The party of Trump, the party that looks like and acts like and supports people like Trump, is already saying Trump is not a true Republican. But if they really believe that, and really nominate someone with deeper conservative leanings in 2020 to try to win a constituency that doesn't exist any more, President Hillary Clinton will have no trouble winning re-election.