The first same-sex marriage in North American history has just taken place. The highest court of Ontario has ruled that the millennia-old definition of marriage of one man and one woman violates Canada's constitution.

How did three people change marriage, always understood to be a privilege defined by society, into a right defined by judges? How can three people have the hubris to overturn a pillar of Western civilization without allowing their society to have a say in the matter?

There is a one-word answer to these questions. Liberalism.

There is no arrogance like liberal arrogance. Nowhere in the conservative world is there anything to match it.

Liberals are certain that they know more, understand more, are more tolerant and more compassionate than anyone else. Therefore, there is no inclination for a liberal judge to allow democracy to determine society's values. The idea that the public should be allowed to vote on one of the most significant issues in the life of a society offends them: Did Moses have the Israelites vote on murder or adultery? Why then would a liberal judge have Americans or Canadians vote on abortion or the definition of marriage?

The liberal American justices who created a constitutional right to kill a human fetus for any reason could not care less what the American people believed about the worth of the human fetus. If nine out of every 10 Americans thought that a woman and her doctor needed a moral reason to extinguish nascent human life, it would only have reinforced the liberal justices' beliefs that America needs their enlightened minds to counteract such foolishness.

So, too, the Canadian justices are quite unconcerned with Canadians' opinions or values. The justices believe that the definition of marriage needs to change, so they changed it. It's as simple as that. They know better because they are liberals.

But liberal hubris runs even deeper than that.

When conservatives are sure of their positions, it is almost always because they believe that a pre-existing and higher source of morality demands that position. To take our present example, conservative opposition to redefining marriage comes from respect for millennia-old values -- those of Western society and those of the Judeo-Christian tradition. Conservatives, of course, may be wrong, but their position is not rooted in belief in self, but belief in a text that they hold far higher than their own opinions and feelings.

Not so liberals. There is no biblical or Western basis for redefining marriage. There is only the individual liberal's high self-esteem: He is so compassionate, so enlightened and so decent that his opinion must surely prevail. The conservative, on the other hand, asks what the founders of his society really meant, what the Bible says, and, yes, what does the citizenry want.

Liberals don't ask such questions. They find the question of what the founders' views were to be irrelevant or even contemptible (the founders, after all, are frequently viewed as economics-driven, white, male slave holders); they rarely care what the Bible says, since they regard it as neither divine nor morally compelling; and they have contempt for the citizenry, as it contains a large number of fools (i.e., non-liberals) to be feared for their lack of enlightenment and education.

What liberals ask is how they themselves feel, not what a text or a founder or a religion teaches. This is one reason liberalism is so attractive. One need not know, let alone wrestle with, prior texts or values. One need only consult one's feelings to know what is right (hence the liberal preoccupation with the word compassion). Indeed, to the extent prior texts are studied, they are done so not to learn from but to deconstruct, i.e., to delegitimize.

Therefore, with no prior religious or national value system to restrain them, liberals are free to invent morality in the image of their hearts.

That is how three people can effortlessly redefine marriage. They felt like it.