“I can’t…” is among the earliest phrases most children learn, and they use it freely, to the frustration of parents everywhere. “But you can,” we tell them. “Just try.” It’s no good. They’ve made up their minds. They can’t. And they don’t. Until, one day, they can and it all seems so easy after all. Adults are little different. “I can’t” can mean so many things. Sometimes it means, “I’ve never done this before and I’m scared I won’t be successful.” Sometimes it means, “I’m not confident about doing this well enough, so I’ll pass in case I embarrass myself.” Sometimes, “I don’t want to be bothered.” Mostly, it means “I don’t want to.” Properly speaking, “I can’t” should only apply when you mean it’s a physical or literal impossibility. You remember those annoying adults who responded to your question, “Can I please have some more ice cream?” by saying something like this. “You can (it’s perfectly possible), but the question is whether you may (is it allowed?). Of course, they were right in their use of English and you were wrong. “Can” refers to capability, not permission. So “can’t” properly means a lack of competence or ability, not unwillingness, fear or laziness. Sadly, people usually believe what they tell themselves. Tens of thousands, hundreds of thousands, maybe millions of people diminish their lives and careers every day by saying to themselves “I can’t” do that, or think that, or speak to that person, or change, or ask for help — and believing what they say. If only they were more careful about their words. If I say to myself “I don’t want to…,” it leaves open the possibility I may change my mind another time. Saying “I’m afraid to…” still gives me the chance to overcome that fear. If I say “I don’t know how to…,” I can always learn. Even if I tell myself “I don’t have enough confidence to…,” the way out of the problem is clear. Precision matters. It shows you the way out. Beware of “can’t.” It has a sound of finality about it, as if you’ve decided for all time that choice or action is impossible for you. That’s how your mind hears it too. Say it often enough and it will become true. It’s fatal to decide on your ability based on short-term emotions like fear and embarrassment, or give in to idleness and lack of willpower. That’s how people get themselves into a state where they “can’t” do anything they haven’t done in the past, imprisoning themselves into a narrow rut where they must spend the rest of their lives. Others have to be coaxed past the dread of “can’t” like a frightened horse. Yet once it’s done, “can’t” evaporates like fog in sunlight. How can you tell if you can or can’t? Forget what you feel or what you believe. Try. Reality gives great feedback. It’s there ready to teach you your true capabilities, your real limitations and, always, what it is you need to do next. Adrian Savage is an Englishman and a retired business executive who lives in Tucson, Arizona. You can read his thoughts most days at The Coyote Within and Slow Leadership, the site for anyone who wants to bring back the fun and satisfaction to management work.