In the 9th grade — freshman year in high school — my history teacher was Mr. Stack, whom I remember being short and solid, kind and wise.

At the beginning of the year, Mr. Stack had the class read chapters by Howard Zinn. It was one of our first lessons. I was awed; stunned at what I was being asked to read. The next day we read, instead, from the high school textbook. Mr. Stack asked the class to compare Zinn’s work to passages from that official history tome. The class debated. Mr. Stack said very little.

At the time I thought I had learned the lesson. Simply put: History is subject to interpretation. And Zinn’s work was an example of a radical interpretation.

Today, looking back, I can’t help but think that I took this lesson the wrong way. Backwards.

Funny. Twenty years later I am still learning from Mr. Stack.