But I don't feel like it gave me permission to save in any sense.
I guess I was thinking the permission aspect has more to do with being permitted to break the traditional definition of working until 55 or 62 or 67 or whatever age was ingrained in each of us as retirement age, as opposed to permission to save itself.
For myself, I have always been a saver and goal driven but I never attached early retirement to why I was saving. I can identify a few reasons (fear of job lost, fear of inadequacy, wanting to have the choice to be a SAHM when time came) for my high savings rate but ER was not one of them until MMM and subsequently reading YMOYL and others.
For me, it changed over time. For most of my career, it was "I want to make a lot of money so I will never be poor again." That, honestly, lasted for a good 20 years -- because even when I was making plenty and saving a good chunk of that, I still didn't have enough to live on permanently. And as long as keeping my house was dependent on a job, I never felt secure. And, TBH, I was ambitious, wanted to prove myself to the world -- and my mom raised me with the expectation that I find something so much I would want to do it my whole life, even if they didn't pay me. Tl;dr: I never did -- but because of that, ER just wasn't even something I conceived of.
Then, thanks to DH's influence, that morphed into "you mean I can actually afford some of those fancy things?" I think "lifestyle creep" is the wrong word; it was more that growing up poor/extremely frugal and not buying things by necessity, I felt great power in being able to, say, go grocery shopping without a list or a budget, or go to an artisan show and buy a fused glass plate just because I loved it, or take the kids to Europe even though the cost of four plane tickets seemed completely ridiculous. This was about the time that I started reading MMM. And, TBH again, my immediate response was "why the fuck would I want to go back and voluntarily live the lifestyle I worked so hard to escape?" [+ I totally adore cars, so it was not exactly love at first sight]
Then a few things happened. My stepdad died, and the ensuing depression was a scourge that stripped me down to the bone; so much of what I had thought was important was revealed as completely meaningless, all about ego and fear. My workload dropped off, and for the first time the thought of throwing myself back out there to build it all back up again struck me as boring and exhausting and not something I really gave a fuck about. And I realized that I wasn't actually poor any more -- that we had saved enough that we could quit if we wanted or needed to, even though it would require some lifestyle tradeoffs. And suddenly more of the MMM message began to resonate: that a lot of the money I was spending was on stuff that did not bring me pleasure or joy or meaning (e.g., generic takeout because I was too lazy/tired to cook); that I had used my job and family responsibilities as an excuse to become mentally and physically lazy, and that I was capable of so much more; that I didn't need to go whole-hog and live on $24K/yr like he did, but that I could decide for my own damn self what I wanted to spend money on (cars!) and what I didn't (bad pre-processed food!); and that I had the ability, right now, today, to quit if I really wanted to -- that it was really my choice whether to walk away from it all, or keep working.
But I also realized that because I had never really conceived of FIRE, I had no clue what I wanted to do with my post-work life -- well, we want to travel, but that requires the kids to be fledged. And DH is not ready to quit at all yet, and my job has gotten more enjoyable since I started antidepressants. So for now, my decision is to keep working while I spend my energy figuring out what is next. But the power in knowing it is
my decision, that whether to work or FIRE is in
my control and no one else's, is pretty life-changing.