I've written in the past on the dangers of the ISM (ideology) - belief systems that ask us to shut down reason and rationality and believe something because it fits into some predefined system of thought. I reject such simplistic thinking because it denies the very real complexity of our world - there aren't many simple answers except to simple problems. What I do "believe in" is discussing things in terms of values.
To me, being liberal is primarily a statement about values. It means I value civil liberties, equal rights, rule of law, education, and a nonprejudicial society. We can disagree on how to realize those values in society but don't you dare suggest that I don't hold them.
Andrew Chrucky wrote "The aim of liberal education is to create persons who have the ability and the disposition to try to reach agreements on matters of fact, theory, and actions through rational discussions."
I'm a liberal because I don't believe people are fully culpable for the circumstances in which they sometimes find themselves (neurological studies have greatly questioned the power of our consciousness). I believe it is the imperative duty and responsibility of those who are capable of acting to help others, to do so. This is why I have no problem with taxation going to support such actions. It IS an imperative and it is part and parcel of our social contract.
We've seen what happens when we rely on charitable organizations, it didn't work, it doesn't scale (it can work in small enough social circles). We know for a fact that people will exploit others for their own personal gain - it's not a matter of rewarding their work. They took people as slaves, beat them, exploited them until they died, raped them, and even raped their children. This is what people, "good Christian people", did when they were not constrained by approprite social pressure. These were the people who ran the largest, most powerful organization of their day. It wasn't a few extremists - it was a dominate corporate enterprise.
It's not a Robin Hood plan either, it's enlightened self-interest. The greater the opportunity for those less fortunate than ourselves to receive education, medical, mental health, and economic assistance the better for our society.
I KNOW for a fact that I benefit from taxation in these ways.
I freely admit there is government waste (that's a huge "DUH"), I disagree that the majority of government is wasteful, that's irrational hyperbole. And I know for an absolute, unquestionable fact that the idea that capitalistic corporations somehow magically minimize waste is a gigantic load of horse shit. I've worked in corporations for nearly 30 years and I've seen massive waste. So try to tell me that companies do a better job, that has been conclusively proven false in numerous studies.
Hopefully this will spark some discussion!