Shakespeare.
A life without bumps is a dull life. -English proverb
The difficult thing is to train a great nanny. Only this cold nanny will keep pushing the cradle and cultivate a brave and energetic child. -Bryant
Not every disaster is a curse; Early adversity is often a blessing. Overcoming the difficulties not only taught me a lesson, but also inspired our future struggle. -Buff.
No wise man will deny the exercise value of pain and sadness. -Huxley
Fire can only turn iron into steel, but it can't burn iron to ashes. -Liu.
Suffering and hardship are the highest schools to temper personality. -Liang Qichao
People's best work is often done in adversity. Mental stress, even physical pain, can be a spiritual stimulant. -Bei Feric.
If a person is afraid of pain, disease, emergencies, danger of life and death, he can't stand anything. Russo.
In the vicissitudes of fate, it is easiest to see a person's integrity. -English proverb