“Trust and verify.”

These were the words of President Ronald Reagan in dealing with the Soviets during the Cold War. Reagan’s words can also apply to the immigration issue currently being debated by the presidential candidates. Opinions on immigration vary from deporting 11.7 million undocumented aliens and having the Mexicans build a wall on our southern border on the conservative “red” side to offering amnesty on the “blue” side of the spectrum.

Why do we Americans, a nation of immigrants, differ so strongly on this issue?

The answer lies partly in how our brains are wired, according to Hannah Holmes, in a TEDx talk in 2014 called, “Red Brain, Blue Brain – the Neurobiology of Political Values.” Her hypothesis is that “red-brained” people see danger in strangers and view people that are different from them with suspicion. “Blue-brained” people see foreigners as fellow human beings who come from other cultures with differing ways of solving human problems. Strangers represent an opportunity to learn and grow. Foreigners represent an opportunity to see life with fresh eyes.

The differences between red- and blue-brained people are on a continuum with those who are in the middle and hold parts of both views. All types are necessary in a society for a culture to survive.

There are real threats outside any culture that must be guarded against. “Eternal vigilance” is the red brain’s motto. Human nature is evil, grasping, greedy and cruel. One needs only to look at the daily news to give ample proof for this: murders, abuse, robberies, rape, war and terrorist attacks head the list. The Hebrew prophet summed up this attitude with his famous quotation: “The (human) heart is deceitful above all things and beyond cure, who can understand it?” (Jeremiah 17:9). This is the perspective of red-brain people.

Of course, some immigrants are angry, violent and deranged. Among those refugees from war-torn Syria who made it to France and Belgium and America, some have killed indiscriminately by spraying restaurants and airports and a Christmas party with machine gun fire, and/or blowing themselves and others up with homemade bombs, trying to maim and kill as many people as they could. Consider Paris and Nice, France, and San Bernardino, Calif.

The response of the “blue-brained” people to this is sadness that a few could act so violently and senselessly. Blue-brained people point out that these extremists are a small minority. Putting all immigrants into the category as violent is not realistic or a true picture of the immigrants who had enough gumption, enterprise and optimism to leave their war-torn homes to start a new life in new lands.

Immigrants bring new ideas and new businesses to refresh the nation with their creativity, hard work and diligence. America became the greatest nation in the world due to these kinds of immigrants. Many are the ancestors of the very red-brained America-firsters, who are the most suspicious of these masses yearning to breathe free.

There are others of us in the middle who can see the arguments from both sides of this continuum. We understand that allowing immigration is a risk, but with careful screening, we will benefit from immigrants far more than they will damage us.

Presidential elections tend to bring the extremes out, because strong opinions and views sell more media than moderation. Candidates want to draw attention to themselves. They point out the supposed flaws of their opponents and often their statements are provocative.

Some of us see threats lurking behind every bush while others of us see learning opportunities and growth with the newly arrived. The challenge of our democratic system is to find the balance between these two extremes.

Ronald Reagan said it best when dealing with Soviets: “Trust and verify.” That should be our mantra. But whatever direction our brains take us, “The ideas in our heads rule our worlds.”