It was the end of a PE lesson, and I was putting my shoes back on. “Mrs Cook, can you tie my laces?” I asked. “Yes,” Mrs Cook said, “I can.” She gave me that teachery look of hers and waited for me to figure it out.
That was when I was seven.
Since then, I’ve become pickier about my modal auxiliaries (can, could, may, might, will, would, shall and should). But pedantic correctness isn’t everything, and sometimes it gets in the way of good communication.
A few weeks ago, I approved some copy for a sign for exhibition visitors. It included a line that went like this:
You may use the cloakroom downstairs.
On reflection, I wish I’d changed it to say:
You can use the cloakroom downstairs.
My thinking at the time was that if you’re talking about permission you should use ‘may’ rather than ‘can’, which is about ability. (This is a rule that a lot of people don’t seem to know or care about, so depending on your linguistic ideology you might not think it’s a rule at all.)
My change of mind is based on pragmatics and tone: explicitly telling people that you’re giving them permission to do something (‘you may’) shows them that you’re the one with the power to decide what they’re allowed to do. It risks coming across as haughty or condescending.
But telling people they have the ability to do something (‘you can’) shifts the right of decision-making onto them. And in a context such as my cloakroom sign, it implicitly gives permission – more gently but no less clearly. (We’d have to be mad to tell people about a cloakroom they’re able but not allowed to use, and in most communication there’s a standard presumption of sanity.)
In fact, just telling people they have a certain ability can in such a case give them that ability. The main requirement for using the downstairs cloakroom is the knowledge that it’s there. The ‘can’ version of the sign gives readers the knowledge and thus the power. It’s not quite a performative utterance, but it’s in that sort of territory.
We can often use ‘can’ to imply permission perfectly clearly and more pleasantly than by stating it directly with ‘may’. Yes we can.