When you look for a job or change careers, what you're really looking for is a way to improve things in your life. But it's hard to figure out what will really make things better and what will only make things worse.

There are some things we all know: People who are in love are happier, and people who are chronically unemployed are less happy. But most of us aren't dealing with such clear-cut extremes.

Most of us ask ourselves on a regular basis, "What's the best kind of work situation for me?" Yes, we're all unique, but in truth we aren't as unique as we think we are. So there are some rules we can all live by when looking for work we'll love.

Forget the deep analysis. Our brains are simply not optimized to figure out what we'll like. Instead, they're optimized to figure out how to like what we have.

This helps us on an evolutionary basis: We eat what's available, we take care of whatever kids we get, and so on. It doesn't help us in a job hunt, where we have to guess what we would like if we had it.

Daniel Gilbert, a professor of psychology at Harvard, spent his whole career studying this sort of problem and published his findings in "Stumbling on Happiness." Gilbert concludes that we're basically unable to know if we'll like a job until we try it, so self-analysis and market analysis aren't going to get you very far. Start trying stuff.

You don't have to quit your job to try things. Try new stuff on the weekend, volunteer for a project part-time, or ask for a temporary appointment to another department, for example. Be creative in how you learn about yourself. A job change doesn't have to be now or never — it can be a process.

That said, here are some guidelines you can use for deciding what you're going to try:

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