can & could

[color=red]A faulty connection could easily cause a fire.

Could we say “A faulty connection can easily cause a fire?” If so, what is the difference between them?

Many thanks.

If ‘can’ suggests 75% of the possibility, then ‘could’ reduces it to 55%, just for example.

To me, ‘could’ is less direct. It indicates possibility in a ‘polite’ way.
‘Can’ is stronger and more direct. Thee outcome is very clear. It indicates abso;ute fact rather than possibility.

I am afraid not. For example, A lion can be dangerous. = It is possible that a lion is dangerous, but not necessarily. Rather, it implies that a lion can be not dangerous depending on the situation.
But I agree to the part of politeness at the same time.

Hi S&S,

‘Can’ and ‘could’ lead different lives. They are often used to express ability to do something as in:

She can swim the Channel = She is able to swim the channel. She could swim the Channel when she was a young woman = She was able to swim.

‘Can’ and ‘could’ are also used to express possibility as in your example: can easily cause a fire. If you change this to: could easily cause a fire, you are suggesting that this happens in a hypothetical (if) situation as in: could (would be able to) easily cause a fire if you didn’t make the right connection.


This is a completely different context. You can just as easily say ‘A lion could be dangerous’.

I am very grateful to all of you for all your help!!!