I don't quite remember when but I read an essay about poetry. It was addressed to this question: What is poetry for? The author said, poetry can be to people what a cup of water is to a man who has spent a couple of days without any water, suffering from heat and dehydration. That is, it can serve as a hope or better, as a driving force to carry on.
This essay was a teaching material for junior high school students. My students at that time didn't seem to make any sense of it, but I did. There is a poem called "the problem of spring（春の問題）" by Yukio Tsuji. I can't cite all of it, but let me introduce to you what it is about.
The poet extends his thought over to the ancient times. The problem of spring is that spring has come again but we don't know how many times it has come since the antiquity. But the primitive men surely didn't know that it was spring. They must know nothing but now. However, they had to know this: he had to survive, and in order to live on, they had to struggle. The poet imagines that they were afraid of struggling even though they knew in their bones that they had to. But he thinks of the fact that the he is today, and he is sure that they surely did struggle and survived in the face of their fear. They fought against their fear. The poet at first felt like admiring them for their fight, but realizing that they are in fact him, and he is in fact them, so he refrained from praising himself.
I think I am in a struggle with my life and I can never get away from it. I am afraid of this fight because it really tests me. It is the test of whether I can live up to what I have declared I wanted to do. Sometimes I want to give up but this poem reminds me that there have been billions of people who fought against their fear and committed themselves to thier life. I don't know how but it always feeds me a fresh courage. It is my cup of water. Spiring will come shortly.