Monomorphic

I thought I’d write a more personal note for a change.

It’s been just over a year since I started studying for my Ph.D. — formally, I entered the program in April 2009. With at least two years to go, how do things look with some hindsight? What do I think it means to obtain the Ph.D. degree, or, more specifically and usefully, to be a researcher in computer science?

Much of what I’m noticing are things that sound obvious and natural, like everyday truisms, when expressed with words, but the idea I have of it goes a little bit deeper than that. For instance, we all get told over and over throughout our lives, starting in high school, that we have to become good communicators. So it’s not going to be a surprise to anyone when I say that I think the process entails becoming a much better communicator than I’ve ever been before. Maybe what’s different is that I am trying to communicate things that haven’t been communicated before, things that I invented — or things that have hitherto been communicated only by a very small number of people. (Most of the communication I did prior to becoming a Ph.D. student may not have been terribly original.) Basically, reading and understanding a large amount of scientific papers, and understanding them with a particular use in mind, either having or getting a sense of how they fit into your own work. Then, writing your own papers, and communicating, somehow, what you thought, and what you were the first person to think, so that somebody else might read it like you read the works of others, and use it similarly. Then, presenting research, discussing it, and understanding what is being presented and discussed by others — similar challenges in speech instead of in writing.

I can’t speak for other fields, but in computer science ( I work with programming languages and software engineering), I find that a lot of this, for me, has been about building up a certain mental dexterity with formalisms. Understanding the implications of formalisms as you read about them and seek to apply them. Communicating formalisms to others. Some of this is still difficult, in particular the “communicating to others” part, but I think I am achieving things in this regard.

Communication, then, where does it take us? One of my mental images of academic knowledge is a big directed acyclic graph (a tree) where papers reference other papers. A surprisingly big part of writing a paper is ensuring that your work can get assimilated into this graph easily — placing it well, referencing the right things, making sure that you can be referenced easily. Also: defining the boundaries of your work extremely well — here’s where it begins, here’s where it ends. We assume precisely this and arrive at precisely that. It really seems that these things can never be made clear enough.

Which leads to another mental image of research: the paper/unit of work as a building block. The more solid it is, and the harder and sharper its surfaces and edges are, the better structures can be built from it (though I think there are other kinds of valuable works too). That’s one direction I think I need to be aiming for as an aspiring researcher.

Many software developers, while making a tool to solve a specific problem, heed the siren call of generality. By making a few specific changes, they can turn the tool into a general framework for solving a larger class of problems. And then, with a few more changes, an even larger class of problems, and so on. This often turns into a trap, and there is a risk that the end of the line is an over-generalised tool that isn’t very good at solving any problem, because the specificity that was present in the first place was part of why it was powerful. In this way, constraints can equal freedom.

Sometimes, though, the generalizers get it right. These are often moments of exceptional and lasting innovation. One example of such a system is the fabulously influential (but today, not that widely used) programming language Smalltalk. Invented by the former jazz guitarist and subsequent Turing award winner Alan Kay, Smalltalk was released as one of the first true object-oriented programming languages in 1980. It is probably still ahead of its time. It runs on a virtual machine, it has reflection, everything is an object, and the separation between applications is blurred in favour of a big object box. On running Squeak, a popular Smalltalk implementation, with its default system image today, users discover that all the objects on the screen, including the IDE to develop and debug objects, appear to follow the same rules. No objects seem to have special privileges.

Another such system is an application that used to be shipped on Mac computers in the distant past, Hypercard. Hypercard enabled ordinary users to create highly customized software using the idea of filing cards in a drawer as the underlying model, blurring the line between end users and developers through its accessibility. I haven’t had the privilege to use it myself, but it seems like this was as powerful as it was because it served up a homogenous and familiar model, where everything was a card, and yet the cards had considerable scope for modification and special features. Even though, in some ways, this system appears to be a database, the cards didn’t need to have the same format, for instance. (Are we seeing this particular idea being recycled in a more enterprisey form in CouchDB?)

There are more examples of successful highly general design: the Unix file system, TCP/IP sockets and so on. They all have in common that they are easy to think about as a mental model, since a universal set of rules apply to all objects, they scale well in different directions when used for different purposes, and they give the user a satisfying sense of empowerment, blurring the line between work and play to draw on the user’s natural creativity. Successful general systems are the ones that can be easily applied in quite varied situations without tearing in the seams.

While not widely used by industrial programmers today, Smalltalk was incredibly influential. In 1981 Objective-C was created by Brad Cox and Tom Love, directly inspired by what the Smalltalk designers had done. Objective-C was subsequently used as the language of choice for NeXTStep, and later for Apple’s MacOS X when Apple bought NeXT. Today it’s seeing a big surge in popularity thanks to devices like the iPhone, on which it is also used. In 1995 Java was introduced, owing a great deal of its design to Objective-C, but also introducing features such as a universal virtual machine and garbage collection, which Objective-C didn’t have at the time. In some sense, both Objective-C and Java are blends of the C-family languages and Smalltalk. Tongue in cheek, we might say that it seems evolution in industrial programming these days consists of finding blends that contain less of the C model and more of smalltalk or functional programming.