Randy sells home improvement services for a major, orange-themed box store. As we chatted about life and careers beyond that which brought him to my breakfast table—my house needs a new roof—he shared a piece of wisdom about sales. It may be the simplest, most important message anyone in sales can remember. And since life is sales (selling ideas, thoughts, beliefs, selves, products, services…), he shared wisdom applicable to anyone who draws breath.

As he explained his sales career in various fields, we discussed the truth of sales versus what newcomers believe when fresh out of college or having completed some sort of training. Admittedly, he and I have many decades of life and observation to rely on instead of merely a couple of semesters of sales classes, but his message is one that people should learn early. Many careers and relationships would be better for it.

“I want you to know everything, but I don’t have to tell you everything I know,” he said.

I believe even the wind paused outside the window when hearing the sublime, but poignant truth.

While his message is similar to many others about “listen more than you talk,” the additional seasoning of sharing information makes for tasty medicine that goes down easily. “I want you to know everything, but I don’t have to tell you everything I know.” Profound.

I cannot think of a single career in which that wisdom would not make a significant difference for both providers and clients: doctors, lawyers, professors, administrators, teachers, sales professionals, financial planners, bankers…the list is endless. I cannot think of a relationship that would not be enhanced by the desire and the humility of the message: parents, friends, spouses…the list is endless.

We all have a lot to share in many ways. It doesn’t mean that we must do so. Sometimes the greatest and wisest application of knowledge and wisdom—just like any power—is to not use it fully.