I'm going to suprise you by agreeing in large part with your post on intentions or what "I really meant". I think I may have confused things by saying original intent. And you are right to point out that 'liberal' and 'conservative' are bad terms, but politically speaking they are what we have to work with. Speaking judicially we might say functionalist or formalist, but no two terms are comprehensive obviously.
To say original intentions is probably the wrong way to put it because there are people who would try to divine the spirit of the law or what the writer really meant as opposed to what he wrote. The 'liberals' (and Justice Thomas occasionally) take this approach (with adverse positions as you point out) to the Constitution, and a vast majority of judges do when it comes to legislation (which, it appears, will suprise you). I agree with you that this is a bad approach. Interpretation must start with the text that was given us.
Let me distinguish originalism from original intent, a distinction Justice Scalia makes. Scalia also eschews legislative history and intent as a bad guide to judicial interpretation for a myriad of good reasons that not enough people take seriously. The extent to which we might try to define original intent is asking "what did those words mean when they were written" or "were these laws commonly thought Constitutional when the article/amendment was adopted." These are legitimate inquiries. So, again, I would probably agree that people of all political stripes may believe they are adhering to some spirit of the law, but this leads to the disputes we have both pointed out, and, I would say, is the wrong approach. In this sense, an originalist's approach is very amoral, which is discouraging to many conservatives BTW, because it rarely allows a judge to invest any overarching intent in the form of moral preferences or authority, i.e. natural law or laissez fair economics, the authors may have held. Justice Holmes was probably the exemplar of this amoral approach.
This is why Scalia says his approach is very simple when it comes to very controversial things. The Constitution simply says nothing about abortion or assisted suicide, etc. Any attempt to force them in there begins by being extra-textual, a difficult hurdle to overcome in Constitutional interpretation. These questions are left to the people and the States, thus, self-government. We have come to the point where we expect the Court to decide every question under the sun. If we think there is a 'right' to something, it must be in there, but this is so self-evidently not the case as admitted by those who want it to be there when they say, "well...ah...ah...the Framer's never anticipated such and such a situation." So what? This seems dispositive evidence that the Constitution does not have an answer the Court, like philosopher kings, may hand down.
