In his introduction to Schopenhauer’s Essays and Aphorisms, translator and scholar R. J. Hollingdale describes the philosopher’s daily routine

From the age of 45 until his death 27 years later Schopenhauer lived in Frankfurt-am-Main. He lived alone, in ‘rooms’, and every day for 27 years he followed an identical routine. He rose every morning a seven and had a bath but no breakfast: he drank a cup of strong coffee before sitting down at his desk and writing until noon. At noon he ceased work for the day and spent half-an-hour practicing the flute, on which he became quite a skilled performer. Then he went out for lunch at the Englischer Hof. After lunch he returned home and read until four, when he left for his daily walk: he walked for two hours no matter what the weather. At six o’clock he visited the reading room of the library and read The Times. In the evening he attended the theatre or a concert, after which he had dinner at a hotel or restaurant. He got back home between nine and ten and went early to bed. He was willing to deviate from this routine in order to receive visitors.

Hollingdale speculates on what this routine might tell us about Schopenhauer’s character and philosophical work:

[…] If we try for a non-emotive description we might call it the inability to abandon or modify an attitude of mind once adopted. Consider the daily two-hour walk. Among Schopenhauer’s disciples of the late nineteenth century this walk was a celebrated fact of his biography, and it was so because of its regularity. There was speculation as to why he insisted on going out and staying out for two hours no matter what the weather. It suggests health fanaticism, but there is no other evidence that Schopenhauer was a health fanatic or a crank. In my view the reason was simple obstinacy: he would go out and nothing would stop him. It is a minor manifestation of that rooted immovability of mind. […]