I've discussed my North Shore Line Theory with a couple of people, and received some feedback which is about as coherent as one can expect, given the somewhat silly concepts involved. I'd like to take this opportunity to pause and reflect — not upon the theory itself, so much, as the ideas that surround it. If nothing else, this may give some insight as to what the heck I was thinking when I wrote that nonsense.

The main theme of North Shore Line Theory is that of the traditional formulation of science. Despite the fact that no serious philosophers of science have held to the traditional (or Baconian) view of science for several decades at least — probably more — it's still a popular view amongst the vast majority who have not studied any philosophy of science. Or, I should say, it's a popular view to the extent that such people actively formulate ideas about the nature of science at all.

Ask the Average Man In The Street what qualities a good scientist should have, and the first answer will probably be "objectivity". Personal bias, he thinks, is antithetical to the scientific method. The scientist must observe data, and the more objective he is in his observations, the better. Implicit in this outlook is the idea that the scientific method is firmly rooted in empiricism. Theories arise from observing real-world phenomena, not from armchair speculation.

I was being a good, strict empiricist with my North Shore Line Theory: it was firmly grounded in objective observation. Not only that, but the theory makes correct predictions all the time. As far as it goes, it's an excellent theory. Even so, there are two obvious problems with the empiricist approach that I've taken.

The first is that I've allowed an assumption to sneak in to my theory: the assumption that the stations on the North Shore Line do not change over time. I've never observed an exception to this, but never observing an exception does not mean that exceptions do not occur. Strict empiricism would allow us only to say that it was constant if we observed it all the time. Even if we have objective observers watching the entire line x% of the time, we can only be x% sure that it remained constant during that time. What about the unobserved past and future?

So I've lapsed in my empiricism with regards to my claim that the line is unchanging. And indeed there are instances where my theory would be proved wrong empirically, but they are in the past and can no longer be directly observed. Before the Sydney Harbour Bridge opened in 1932, the line took a different route at the southern end, terminating at the harbourside rather than crossing the bridge as it does now. My theory would have been rather different if I'd observed this change in the line, but I had no such opportunity: the line has been static for considerably longer than I've been around to observe it.

Even so, the assumption that the line is static happens to be true nearly all the time, and it is absolutely necessary to have an assumption of this sort if the theory is to make any predictions. Pure empiricism can only tell us what happened when we observed something in the past, not what will happen in the future. Clearly science can't be purely empirical, or it would be devoid of predictions.

My co-nutter, David Nelson, suggested that I should have a theory of station-creation to bolster my claim that the line is static, or at least give some indication of how static we can expect it to be. But here, again, empiricism lets me down: there aren't any stations being built or destroyed on the North Shore Line at the moment, so I can't make the observations necessary to produce such a theory. The last station to undergo any kind of modification was St Leonards station, and observing that process would have gained me nothing: the old station was closed and replaced with temporary platforms just to the south; the new station was built on the site of the old; the new station was opened and the temporary platforms removed. My North Shore Line Theory would have been true throughout the entire process (as St Leonards remained between Artarmon and Wollstonecraft at all times), thus perhaps misleading me into thinking that station creation was not important to the theory.

And that brings us to the second problem. Empiricism (plus assumptions) can grant us the ability to make useful and accurate predictions, but it doesn't really grant us any understanding deeper than the observations themselves. If all I knew about the North Shore Line was the order of the stations and the fact that the order was static, I wouldn't have much understanding of it. In order to gain an understanding of the system, I have to start constructing imaginative stories about why the facts are the way they are, and that kind of "imaginative storytelling" is verboten in the traditional view of science.

Clearly the traditional view of science is incomplete and partly wrong, but also, it must be emphasised, partly right. I did come up with a mostly true and entirely useful theory utilising the traditional approach, but in some sense I had to break my own rules, and the potential for further understanding utilising this approach is limited.