As the presidential campaign enters the home stretch, the battle lines have been drawn in sharp relief. Policies and, more often, personalities have been the subject of harsh and loud criticism, to the extent that it can be difficult even to hear what the opposition is saying.

Of course, in partisan politics, there is a tendency to hear what one wants to hear, but it must be said that this year’s Republican convention featured speakers and speeches dedicated more to vitriol and sarcasm than to substance. Former New York Mayor Rudy Giuliani and Alaska Gov. Sarah Palin, especially, launched direct and ad hominem attacks on the Democrats and their presidential nominee, Sen. Barack Obama.

If you are an independent voter who tuned in to the Republican convention, what you heard should have been disturbing on many levels. I’m speaking not of policies and resumes — although there’s much to say on those subjects — but of attitude and approach, of tenor and tone, that, if indicative of the GOP’s approach to governance, bodes ill for the nation’s progress.

To be sure, Sen. John McCain, in his acceptance speech, sought to position himself as a bipartisan maverick, an individualist who regularly reaches across the political aisle to form effective coalitions. Yet his remarks were marginalized by the prior days’ convention activity. Indeed, the lasting impression left by the GOP convention was not one of collaboration, but of divisiveness and ridicule.

Politics, particularly presidential politics, is a contact sport and certainly no place for sensitive souls and shrinking violets. So, as distasteful as negativity, sarcasm and anger may be, the most salient reason to be wary of the Republican ticket is not merely aggressive partisanship, but the spirit of disrespect and anti-intellectualism, and the utter lack of understanding of community service, that imbued so much of the GOP convention.

For decades we have encouraged our young people to pursue higher education, to strive not for mediocrity but for excellence. Our parents sacrificed, and we ourselves sacrifice, to send the next generation of students to college and beyond, and encourage them to engage in lifelong learning, so that they will be better equipped to succeed in a complex global business environment and an increasingly interdependent world.

But what did we hear at the Republican convention? Repeated denigration of Sen. Obama’s Harvard education and his stint as a law professor, and backhanded slaps at his work as a community organizer, all delivered with a wink and a smirk.

Isn’t community service desirable? Community organizers play a vital role in helping our neediest citizens and in plugging gaps in the social safety net. Isn’t it admirable that our best and brightest can be motivated to forego the big money and to get their hands dirty in the trenches? When did community service — think Vista, the Peace Corps, Service Corps of Retired Executives, Job Corps, AmeriCorps — become reviled, the choice of losers who supposedly can’t handle accountability?

And when did higher education become a stain on an individual’s resume? When did it become more desirable to have less education, and at less prestigious institutions of higher learning?

There’s nothing that says education guarantees effectiveness, and there are certainly individuals who haven’t had the benefit of higher education who have achieved a great deal, but surely core American values continue to include education, aspiration, service and selflessness. A political party that seeks to govern this nation should not build a case for its candidates by ridiculing those who have chosen a path that we have for generations considered vital to America’s future.

There are innumerable points of departure between the Democrats and the Republicans with regard to policy. Those policies are and should be the subject of deep and consistent discussion at this critical time in the nation’s history.

But it is no less critical for voters to consider the underlying philosophies that form the foundations of the parties’ positions.

At a time when we are in fierce global competition for the best and brightest workers, the most dynamic and innovative companies, the scientists and researchers of greatest potential, can we afford to choose leaders who seem to regard education and public service as negatives, and who regard thought and analysis as reflections of weakness?

Supporters of Sens. Obama and Biden already know what they see in their candidates, and why they will vote for them. But independent voters who are wondering what life would be like under a McCain-Palin administration should consider whether such an administration would not only possess the skills and talents necessary to succeed as leaders of our country, but also whether it would reflect the civic values that we have sought to imbue in our children as Americans.

Perry B. Newman of South Portland is an international business consultant and writer.