This blog began about two years ago when I first started seriously considering graduate school. At the time, I was envisioning being a full-time student and living on half my income, so simplification seemed like great preparation! However, things took a different course, and now I'm doing grad school online (through a reputable univeristy) and working full-time. I don't need to simplify the finances, I need to simplify time!
However, many of the principles for minimizing stuff and purchases are also applicable to minimizing activities and time commitments.
My philosophy for possessions and purchasing is "Don't own stuff you don't like." Slightly tweaked for time commitments, this would be "Don't do stuff you don't like." Just typing that, I'm thinking, "Well duh, why would I do something I don't like?" It happens all the time though. We all have to do some stuff we don't like (emptying the dishwasher, getting the oil changed, etc.), but for discretionary time, we do often decide to spend our time doing things we don't like for various reasons. The biggest reason though is the general inability to say "no" to activities. Other people are exceedingly good at manipulating our time since it's not often treated like the valuable commodity that it really is.
One of the aspects I group into my overall stuff philosophy is not owning stuff that gives you a bad attitude or brings out bad memories. The same goes for time commitments. There's no point in engaging in activities that bring you down, make you mad, or otherwise cause general frustration. Sometime this could be the activity itself, sometimes it could be the people we're doing it with. Is that unfriendly, mean and kinda selfish? Yes. But it's my time, I get to chose!
So- first tier for me minimizing activities: "Do I like this activity?"
Another principle of stuff-and-things minimizing is examining the return on investment on objects. Relating this to time commitments, I get to analyze the return on investment of my activities. What activities are moving me forward in my personal and professional goals? What activities help me adequately rest and relax? What activities are simply time sucks? What activities help other people?
Second tier: "Does this activity actually benefit me or someone else?"
Living in a world with little time margin available, the business principle of opportunity cost comes into play. In the world of purchasing, opportunity cost means "By buying this item, what am I giving up the opportunity to buy?" So with time management this translates to "By pursuing this activity, what other activities am I giving up?" This is one of the hardest principles for me to follow. I can talk myself out of buying just about anything because I know I'd rather spend money on something else. But thinking "I need to forego a gathering of friends so I can finish this school project" is quite hard. Friends are way more fun!
Third tier: "Is doing this activity going to cost doing other important activities?"
In terms of practical application, here's what I've boiled my activities down to in the last few months:
Daily life chores
Select friend gatherings
Anything else happens on an as-needed, convenience basis (including blogging, heh, sorry). It's a bit draconian at times and I've had to start saying "no" to activities, thus causing a few moments of "I'm a terrible person!" but it's really been ok. I'll catch up in 2.5 years or so when the Masters is done :)