I have a limited capacity for doing hard things. Basically, I can manage two or three hard things at once. Any more than that and only two or three of them get done.
What do I mean by hard things? I mean activities and processes that require attention and willpower. I’m not so much talking about things that require effort or energy if I already understand how to achieve them. The hard things are things that I am figuring out how to do as I go, or which require constant vigilance to achieve, or that need consistent imaginative input.
Writing a book is a hard thing, although how hard depends on the phase of the work. Controlling my diet is a hard thing. Some parts of my day job can be hard things (akin to parts of writing a book, really, which is no surprise to me).
My hypothesis is that this limited capacity is related to the phenomenon of decision fatigue: there are only so many decisions you can make in a day or an hour before your brain is tired and can’t do any more deciding. This is why so many successful people have simple wardrobes: wearing the same thing every day means not having to waste decision capacity on choosing your clothes. The same thing goes for willpower – exercising your willpower increases your potential willpower in the longer term, but each use of your willpower reduces the strength of will you have left for the rest of the day.
All of this is to give myself some credit for trying hard things rather than punishing myself for not doing more. There’s only so much a brain can manage.
But I need to be more vigilant (which itself is a hard thing) about taking more hard things than I can accomplish. Ambition is good, but only when focussed.