First, I went to Guatemala and taught SAT prep 12 hours/week with 3 day weekends. This gave me the status of having a job, personal fulfillment of making a positive impact on students' lives, and paid far more than what I needed to cover living expenses. I spent my days reading suspense/fantasy novels, trail running, bike riding, volcano climbing, hanging out with friends, exploring, and seeking new experiences. Life was like a full time vacation!

Now, I'm here in California, "working" as a nanny (still have 3 day weekends), and my job consists of taking care of 2 fun, hilarious, well-behaved boys, playing marco polo, having nerf gun wars, buying and cooking whatever I want, reading bedtime stories, and it gives me the personal fulfillment of feeling super appreciated. In my free time, I play board games, go hiking, play ultimate frisbee, catch up with friends, and do loads of reading. Life is like a full time vacation!

That sounds completely awesome! I've always imagined that sort of lifestyle, but it always felt too abstract. Reading your description has helped my understanding become more concrete and vivid. Thanks you.

Can a good argument be made in favor of ambition over hedonism, or does it all just boil down to intrinsic motivation and feelings of personal satisfaction?

Ok, so the following is the state of my beliefs and understanding. In a way, I feel rather confident in it, because I've done a good amount of reading into other arguments, and after doing so I still think my reasoning makes more sense. But on the other hand, I definitely notice confusion, enough such that I wouldn't describe myself as "very confident". I wrote about it a bit more in depth here and here, which you might be interested in. It's about as well as I could articulate it without spending weeks writing and researching.

Summary - Morality is sort of a question asking about what you should do. Someone might say, "you should do X" or "you shouldn't do Y". My response - "should requires an axiom". You can only say, "you should do X... in order to achieve this end". Or "you shouldn't do Y... in order to achieve this end". The way people use the word, they're usually referring to an end implicitly.

Then there's the question of "well, what should the end be?". Which is circular. Consider two things though:

1) Preferences

2) Goals

Your Preferences are what produce the most desirable "mind-states". Imagine a thought experiment where you take a person, stimulate his brain to produce a bunch of different mind-states and have him rank them according to how preferable they are. This is what I'm mean by Preferences.

Goals are what you choose to strive towards. For example, you may choose to strive towards being a good mother, even if it doesn't maximize your Preferences.

You could choose whatever Goals you want. Preferences are pretty fixed though (seemingly).

Anyway, I don't think there's really an answer to "what Goals should you choose?". You have to say, "what Goals should you choose... in order to achieve this end". Goals are arbitrary. Rationality is about doing the best job you could at achieving the Goals you choose, but it doesn't help you actually choose them (because they're completely arbitrary). I've heard attempts to side-step this, and I've never been convinced. But like I said, there might be something I'm missing (I really hope there is).

Ambition vs. hedonism

Some people frown on a lack of ambition.

• If pleasing these people is part of your Goals, then being ambitious will help you to achieve that Goal.
• If not being ambitious causes you some sort of guilt or other form of unhappiness, then in order to achieve the Goal of maximizing your Preferences, it'd make sense to either a) change that fact, or b) become more ambitious.

To be practical:

• Altruistic acts tend to make people happy, and are one of the biggest correlates of overall happiness. The opportunity cost of zero ambition is that happiness you could have gotten by pursuing an attempt to help people. For most people, to maximize happiness, I think it's worth spending a good amount of time trying to do good. (Of course, then there's the question of how to do good, and what to do when you're faced with the choice between warm fuzzies and things that produce more a lot of good, but don't produce as much warm fuzzies.)
• Humans tend to care about how others view them. How much you care seems rather unchanging to me, although I don't know what the true determinants of "the elasticity of caring" are. I think that for most people a good rule of thumb is to consider how much you currently care about how other people view you and take that into account when trying to achieve your Preferences.

Also, Ambition can be poison (one of my favorite posts). I think it's a very slippery slope. Personally, I've fell pretty far down the slope and am trying to climb back up a bit.