Some people have trouble doing meaningless intellectual pursuits like crosswords, sudoku etc.

Working on Colorforth might be the greatest meaning in his life.

Still the same dichotomy. Who's to say his other pursuits are "meaningless", and the likes of crosswords, sudoku, etc.? For all we know he might have some other projects that he considers more useful.

He does not think working on Colorforth is worth it anymore, so it could actually be detrimental to do so.

I suppose there's meaning in searching for abstract logical truths, but he might have other such pursuits. Or, he might even feel that it's mostly done already and became just another boring software maintenance project.

It's hard to imagine an extremely niche software tool to be the greatest meaning in someone's life.

He himself said he didn't think it was worth it anymore and that he very rarely codes now. I respect him enough to assume he has some other pursuit more worthy of his attention.

>> Some people have trouble doing meaningless intellectual pursuits like crosswords, sudoku etc.

My Dad is like this. I'm like this. My son is like this.

Unless we're busy, pushing ourselves to build something, fix something or just outside doing something we don't feel the reward.

My Dad told his motto, "A rolling rock gathers no moss - until it finally stops rolling." He told me that in his 50's - he's in his 80's still out in the garage refinishing old furniture and giving it away. The drive the man has just never burns out.