In his twenties Hakuin drove himself into a physical and mental collapse that he described in detail: burning feet, freezing head, ringing ears, terror, exhaustion, an inability to practise at all. He called it Zen sickness and attributed it to forcing the energy of practice upward through sheer effort. The cure he credits to a hermit named Hakuyu, who taught him a contemplative method of settling attention below the navel and imagining a soft healing butter melting down through the body. He published the account decades later in a book called Idle Talk on a Night Boat, and it is one of the very few frank descriptions in the literature of meditation practice going badly wrong.
The second half of his life was spent almost entirely at Shoinji, a dilapidated temple in his home village. He declined the prestigious metropolitan appointments that came to him, taught farmers and townspeople alongside monks, and wrote in colloquial Japanese and in popular song form so that people who could not read Chinese could follow him. He also wrote letters attacking a local lord over the taxation of peasants.
He drew and wrote constantly, producing thousands of paintings and calligraphies, given away rather than sold: blind men crossing a log bridge, an enormous rough character, a monkey reaching for the moon in the water. They are deliberately unrefined, and they were teaching instruments rather than art, which is a large part of why they are now treated as art.