ない

ない

"ない" means "not" or "nonexistent," used to indicate negation or absence.

In this context, 'ない' is being used as a negation of the idea that something will happen.

彼は遅れることはない。

He will not be late.

Here, 'ない' negates the action of '行く' (to go), indicating that the action is not going to take place.

今日はどこにも行かない。

I am not going anywhere today.

In this example, 'ない' negates the potential possibility that 'forgetting' will occur.

忘れてしまうこともない。

It is not that such things are forgotten.