One day Dogen instructed,

The distinction between being brilliant or dull applies only when thorough aspiration has not yet been aroused. When a person falls from a horse various thoughts arise before he hits the ground. When something occurs which is so serious that one’s body may be damaged or one’s life may be lost, no one will fail to put all his intellect to work. On such occasions, whether brilliant or dull, anyone will think and try to figure out what is best to do.

Therefore, if you think you will die tonight or tomorrow or that you are confronting a dreadful situation, encourage your aspiration and you will not fail to attain enlightenment. A person who seems superficially dull but has a sincere aspiration will attain enlightenment more quickly than one who is clever in a worldly sense. Although he could not recite even a single verse, Cudapanthaka, one of the disciples of the Buddha, gained enlightenment during one summer practice period because he had earnest aspiration.

We are only alive now. Only if we learn the buddha-dharma, earnestly wishing to attain enlightenment, will we be able to do so before dying. (Shobogenzo Zuimonki, Book 2, Chapter 20)