Cannot & Can Not

Several words of the English language tend to confuse natives as well as non-natives with regards to their spelling. And, sometimes, there isn’t even an ultimate answer to the question of how to spell a certain word. In the case of ‘cannot’ and ‘cannot’ however, there is a very convenient answer:

 

They are (almost) interchangeable!

 

Both versions of negating can are found throughout literature and more informal writing, yet ‘cannot’ seems to be the much more usual and preferred variant.

 

Anyhow, some word-processing programs’ native spell checking tools still mark ‘can not’ as being wrong. A good spellchecking tool, however, accepts both variants:

Some distinctions

Still, there can be some distinctions made between the usage of ‘cannot’ and ‘can not’.

 

One possibility is to look at ‘cannot’ expressing that there is no other choice or option available, whereas ‘can not’ leaves another option open.

He cannot/can not eat another slice of pie.

The usage of ‘cannot’ would imply that “he” is completely and utterly unable to eat another slice of pie. The usage of ‘can not’, however, implies that “he” indeed could eat another slice, but that “h” is simply full.

 

Another possibility is to say that ‘cannot’ is used in general, while ‘can not’ is used if the negation belongs to another constituent.

She can not only play guitar, but also sing like an angel.

The third distinction can be made by saying that ‘can not’ puts a special emphasis on the negation.

Can he fix the car?
No, he can not fix the car!

What about ‘can’t’?

Usually, one would say that ‘can’t’ has to work similar to ‘didn’t’ or ‘don’t’, which are typically combinations of two words (namely ‘did + not’ and ‘do + not’). This is not the case with ‘can’t’. Instead of being a contraction of ‘can’ and ‘not’, it’s more likely a contraction of ‘cannot’.

 

So what do I do now?

Blatantly said? It doesn’t matter. If you want to be on the safe side though, here’s an easy rule of thumb:

 

Use all variants (can not, cannot, and can’t) in informal writing.
Use ‘cannot’ in formal writing.