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How Software Engineering Differs From Computer Science
cconnell sends in a piece he wrote for Dr. Dobb's which "argues that software development will never be a fully formal, rigorous discipline, and the reason is that software engineering involves humans as central to the process." Quoting:
"Software maintainability, for example, is the ability of people to understand, find, and repair defects in a software system. The maintainability of software may be influenced by some formal notions of computer science — perhaps the cyclomatic complexity of the software's control graph. But maintainability crucially involves humans, and their ability to grasp the meaning and intention of source code. The question of whether a particular software system is highly maintainable cannot be answered just by mechanically examining the software. The same is true for safety. Researchers have used some formal methods to learn about a software system's impact on people's health and property. But no discussion of software safety is complete without appeal to the human component of the system under examination."
I'm not sure if I want to reply to AC's, but I forgot to mention I'm a structural engineer myself by education... Most structures of respectable size fall back on Finite Element Analysis to gauge the response to a variety of loads. [The estimation of loads is a research topic in itself, where the factors of safety comes from a rigorous stochastic-based reliability analysis]. Once analysis has been performed, design is a bit of intuition, but certainly not estimation - it's more of heuristics... so you say, "this worked last time, let me try this option and analyse if it'll work this time too."
Soft skill? Depends how well it's done. Lets use car repairs as an example. There are many times I've known or heard tell of where well trained city mechanics throw up their hands in defeat before the car is taken to either a 'mate who knows something about cars' or a 'bush mechanic' and fixed in 15 minutes. Ie. Sometimes the ability to observe, sort information well and problem solve is worth a lot more than a piece of paper with 'engineer' written on it.
Another example. I run a computer repair business with a 'no fix, no fee' policy. Even though I've never had a single day of formal training in the field, I have never, ever had to bring that policy into action. Meanwhile it's surprising how often my mates who have done IT or computer science ask me for help on something because they just don't know how to THINK.
sudo mount --milk --sugar
Going by the wikipedia definition, decisions made in typical software development cycles don't seem to rely on a justification based mathematical or physical analysis. Admittedly I might be generalising, but is it more of a soft-skill then?
That's just horsepucky.
The only reason it seems the way you mention is that software processing cycles are so ridiculously cheap compared to, say, 3" C-Channel girders. But just today, I was doing some engineering to develop a distributed, self-healing clustering file system. Specifically, I was doing performance analysis of different approach, doing a base unit of 1,000 simple file reads. That is most *definitely* a physical analysis - performance tuning always is. But do I care about each individual line? Not really. Do I do extensive analysis of each individual element? Not by a long shot, simply because the actual, real, overall cost of the software is so low.
We host highly complex, vertical-market database solutions. We have a pretty decent hardware cluster comprising some $25,000 in whitebox rackmount equipment. A nice half-rack of stuff. And another $10k or so for a failover DR scenario. But compared to the number of customers we service, and the size of my company, that's an insignificant investment, yet we are overbuilt at least 400%!
If 3" C-Channel cost $0.05 per linear foot, how much checking would you do beyond "good enough"?
I have no problem with your religion until you decide it's reason to deprive others of the truth.
Science (like religion) is in some sort of ideal world, vacuum, where all is simple and described by a formula.
I think you're confusing (or conflating) science with mathematics. But don't feel bad; people do this all the time. Part of the reason is that science routinely uses mathematics as a tool, and the two fields are deeply intertwined. Scientists use math to help understand and explain what they're working on, while mathematicians routinely use scientific work as inspiration for new ideas to pursue.
But the "science" part is usually very much about the real world. It's the mathematicians who carefully avoid dealing with the real world, since that's not their job. The interesting part is how often the abstract, theoretical stuff that the mathematicians work on turn out to be very applicable to figuring out what's going on in the real world.
One of the problems with our terminology is that "computer science" is generally used for the abstract, theoretical part of software. This is misleading, because the subject really is a mathematical field, not scientific. If it were scientific, the computer scientists would be performing experiments and developing hypotheses to explain how software works. But that's not what they do; it's the "software engineers" trying to debug software that do things like that.
And this leads to the problem that "software engineering" generally involves doing things that in other fields would be called "science". In engineering, you are generally working with tools and materials whose behavior is well understood, so you can concentrate on design. With software development, this isn't generally true. An engineer designing a bridge or house or airplane can expect to work with detailed specs for all the available components. With software, the equivalent information is usually proprietary and intentionally hidden from the people building the code. Even in "open source" systems, the concept of "information hiding" is popular, and all too often this does mean that needed information is intentionally hidden from the person writing the code. So the software engineer is working with poorly-documented material, and must develop using processes that test and discover the properties of the underlying stuff.
Of course, there are some software engineers who don't do any debugging. But we know how well this works. Civil engineers might be able to develop this way, since they have access to full specs for their material. Software engineers can't, because they are kept ignorant of the details of lower-level stuff. As long as this is true, software engineering must have a large scientific component, to study and test the software as it's developed. They must constantly develop and test hypotheses about their code, in order to get it to function as desired in an environment that is mostly hidden.
Anyway, there's little chance of getting the terminology straight any time soon. There's no chance of software people getting access to detailed specs for the underlying systems. We even have laws in place that block the access to full information. So software engineering can't really be true engineering, and software developers will continue to spend large parts of their time acting as experimental scientists in order to debug their software. And they won't get much help from the computer scientists, who are spending most of their time working with the mathematics of the subject, while disparaging the real-world portion of their discipline as being "mere engineering".
Now if we could only get the computer field to adopt the same definitions that other fields of engineering, science and mat use. But that isn't going to happen any time soon.
Those who do study history are doomed to stand helplessly by while everyone else repeats it.