1. 4 hours a day has been widely reported as the limit
2. The book Daily Rituals reports high achievers doing 4 hours really hard work a day.
3. Personal experience. Steep drop off after more than 4 hours; burnout after a few days much over 4 hours, etc.
4. Very few examples of people going over that number sustainably.
I suggest people track this themselves and see what happens.
I find I can get to 4.5-5 hours maybe with a lunchtime nap. Maybe much more with lots of micro-naps (doze in chair for 5 minutes).
Currently I am experimenting with turning 24 hours into two days with a long nap in the middle. I am having trouble doing this though.
N.B. This is not 4 hours of any kind of work. This is work at the maximum of intellectual effort e.g. deliberate practice, learning to ride a bicycle, memorizing vocabulary with Anki decks, practising a foreign language at the limit of your comprehension, trying to prove theorems, doing exercises on a hard scientific subject you are learning, writing at the top level of quality and/or on difficult topics, etc.
Follow up on Herbert Simon. From his book “Models of my life”
Worked 60-80 hours a week. But does not detail what “work” means.
When collaborating with someone he comments that most of his day’s work would be usually done by 10am, about the time his collaborator would be getting started. This perhaps hints that early in the day he did a few hours of really hard intellectual work.
What HS regarded as hard work may differ from other people. For example he learned about 20 languages to the point of being able to read papers, and 4-5 to the level of reading literature. But he regarded this as a fun/hobby thing.
He had a problem of hobbies turning into work, and had to drop several of them (e.g. playing musical instruments).
At college he only did enough work to get graded at A. Early on he spent too much time playing ping-pong and his grades slipped.
He published ~1,000 papers and 37 books and accrued to date over 350,000 citations. So he was amazingly productive.
He spent a lot of time on office politics and other managerial and administrative things.
He found writing easy and so wrote many/most of the papers he was a collaborator on.
Conclusion: HS was very smart, very productive, found things that were challenging for others to be fun/hobbies, and while it seems he did work long hours, it is not clear how much time he spent at the highest level of effort. There are hints he did concentrate his top tier work in the first few hours of the day.
is there a reason you’re anchoring at 4 hours in particular?
Why 4 hours?
1. 4 hours a day has been widely reported as the limit
2. The book Daily Rituals reports high achievers doing 4 hours really hard work a day.
3. Personal experience. Steep drop off after more than 4 hours; burnout after a few days much over 4 hours, etc.
4. Very few examples of people going over that number sustainably.
I suggest people track this themselves and see what happens.
I find I can get to 4.5-5 hours maybe with a lunchtime nap. Maybe much more with lots of micro-naps (doze in chair for 5 minutes).
Currently I am experimenting with turning 24 hours into two days with a long nap in the middle. I am having trouble doing this though.
N.B. This is not 4 hours of any kind of work. This is work at the maximum of intellectual effort e.g. deliberate practice, learning to ride a bicycle, memorizing vocabulary with Anki decks, practising a foreign language at the limit of your comprehension, trying to prove theorems, doing exercises on a hard scientific subject you are learning, writing at the top level of quality and/or on difficult topics, etc.
Having said all that, there is a crying need for more work in this area.
The current lead I am following up is Herbert Simon. Will also check out Knuth.
Someone suggested Flaubert, who worked 12 hours a day. And produced 0.7 (really well honed) words per hour.
Follow up on Herbert Simon. From his book “Models of my life”
Worked 60-80 hours a week. But does not detail what “work” means.
When collaborating with someone he comments that most of his day’s work would be usually done by 10am, about the time his collaborator would be getting started. This perhaps hints that early in the day he did a few hours of really hard intellectual work.
What HS regarded as hard work may differ from other people. For example he learned about 20 languages to the point of being able to read papers, and 4-5 to the level of reading literature. But he regarded this as a fun/hobby thing.
He had a problem of hobbies turning into work, and had to drop several of them (e.g. playing musical instruments).
At college he only did enough work to get graded at A. Early on he spent too much time playing ping-pong and his grades slipped.
He published ~1,000 papers and 37 books and accrued to date over 350,000 citations. So he was amazingly productive.
He spent a lot of time on office politics and other managerial and administrative things.
He found writing easy and so wrote many/most of the papers he was a collaborator on.
Conclusion: HS was very smart, very productive, found things that were challenging for others to be fun/hobbies, and while it seems he did work long hours, it is not clear how much time he spent at the highest level of effort. There are hints he did concentrate his top tier work in the first few hours of the day.