I've slipped from "conservative deliberation" to "genuine, true deliberation." There is no difference, and if you think otherwise, you're mistaking the semblance for the real thing. There is nothing that would count as evidence that a course of behavior or way of life that went against what we know to be true about our nature and our set of time-honored, human-nature-tested and cherished values was the right course or a good way of life. For the only kind of thing that counts as evidence in these matters is what we prefer, what suits us.
Deliberation in a healthy forum is the attempt to determine a course of action or policy which maximizes the fulfillment of an array of parameters - values which, due to the vagaries and limitations of circumstance, cannot all be perfectly fulfilled all of the time (or even any of the time.) This is prudential reasoning about what is important to us (such as decency, justice as getting what one deserves, prosperity, security, freedom) in effort to preserve as much of it as we can. It is like the individual's prudential reasoning over what is important to him, in which he attempts to fulfill as many of his desires as possible. Logical and circumstantial coherence constraints guide this reasoning, as for example, when we notice that an increase in security is inconsistent with maintaining liberty and prosperity at current levels. This is case-based reasoning. It applies principles only as rules of thumb or heuristics, which are nothing more than gestures at a host of non-controversial cases about which all parties to debate are expected by the applier of a principle to agree.
The array of values map onto our preferences and are suited to our functional dispositions. The mapping isn't mechanical, as the array itself has gone through the civilizing process of the aforementioned deliberation over and over again in a tradition (as, for example, when we ferret out incoherent values that ill-fit the rest of the array, such as the value that sanctions a man's right to keep innocents as slaves.) In other words, human nature doesn't come off the rack perfectly smooth in it's internal coherence of desires. This coherence is won and urges natural to us tamed by reflection upon more powerful urges also natural to us. The point is that deliberation in a healthy forum is this process of seeking coherence amongst our array of values and determining actions which cohere with that array by maximizing its net fulfillment.
This is procedural conservatism, the epistemic side of the heart of conservatism. Therefore only conservative deliberation is healthy deliberation. Normatively speaking, only conservative deliberation is deliberation.
The alternative to conservative deliberation is the development of absolute principles or rules in isolation from human nature, from the array of things which are important to us, and from the messy business of facts, history, and various contingencies uncovered by lengthy exposure to case-based reasoning. It is favored by leftists and libertarians. The former fetishize economic equality and state power, whereas the latter fetishize liberty. They cling to the fulfillment of their fetish, come what may. Facts in conflict with the sanity of these approaches are explained away. This is dogmatism. It isn't deliberation.
Now, I don't mean to stigmatize all leftists and libertarians, but only those who have completely lost their hold on healthy deliberation. Some, on the other hand, have not. They are conservatives with eccentric views. They engage in procedural conservatism, unlike their dogmatic kin. But they see things idiosyncratically and cleave to redistribution and state power or to liberty much more often than other conservatives in the forum. They do not fetishize their conclusions beforehand but arrive at them legitimately.
There is a lot more on this sort of thing in the archives. I'll have more posts on it in the future.
We're moving on to Mill's On Liberty next.
UPDATE: The remarks I made about eccentric views indicate that I'm not saying that conservatives are the only genuine deliberators in the forum. When you meet someone who is espousing what are not conservative views, he may be a conservative in the procedural sense. He is a genuine deliberator. Most leftists do not match this description, however. In my experience, almost all have been dogmatists.