Most of what we know about sales comes from a world of information asymmetry, where for a very long time sellers had more information than buyers. That meant sellers could hoodwink buyers, especially if buyers did not have a lot of choices or a way to talk back.

There's an idea out there that salespeople have actually been obliterated by the Internet, which is just not supported by the facts.

But in the end, mastery involves working and working and showing little improvement, perhaps with a few moments of flow pulling you along, then making a little progress, and then working and working on that new, slightly higher plateau again. It's grueling, to be sure. But that's not the problem; that's the solution.

What's important now are the characteristics of the brain's right hemisphere: artistry, empathy, inventiveness, big-picture thinking. These skills have become first among equals in a whole range of business fields.

Abstract thinking leads to greater creativity... But in our businesses and our lives, we often do the opposite. We intensify our focus rather than widen our view.

Anytime you're tempted to upsell someone else, stop what you're doing and upserve instead.

We have this myth that extroverts are better salespeople. As a result, extroverts are more likely to enter sales; extroverts are more likely to get promoted in sales jobs. But if you look at the correlation between extroversion and actual sales performance - that is, how many times the cash register actually rings - the correlation's almost zero.