Developer Interview

In preparation for the release of Deductions 1.1, I completed an interview that might be of some interest:

Question: What’s the most unique, useful feature of Deductions?

Wandering Mango: I’d have to say the most useful feature is different from the most unique feature. The most useful feature is that Deductions gives you immediate feedback on proofs; it lets you know whether you made a mistake right away. The most unique feature is the hint engine. Often, when you’re working on proofs in logic, you can get stuck. The hint engine gives you an idea how you might solve the problem.

Q: Why did you create Deductions?

WM: I created Deductions because I have always been fascinated by computational logic, and because the vast majority of natural deduction apps lack a modern look and feel. When you look at the other natural deduction programs that are on the market, most of them are antiquated. They are written for DOS, or Windows 95. Some are rudimentary Java applets. As you might expect, these programs tend to be awkward and primitive. I wrote Deduction to have an intuitive user interface, and to be a modern alternative.

Q: What is most interesting to you about developing software for the Mac platform?

WM: What is most interesting to me is the attention to design. From the Cocoa framework, to separation of the view and model, to the polished user interface that users expect, the Mac development environment is something really special. I’ve worked on other platforms, and so I really feel like I’ve come to a place where people are very interested in what your program does and how your program does it. It is the interest in “how” that sets the platform apart.

Q: What features should a prospective buyer look into during a trial of your product?

WM: A prospective buyer should have a look at the video tutorials, and then if you know anything about natural deduction, run through some deductions to see how the program helps you learn. Deductions is a great tool, and this will give you a good idea how and why.

Q: What are some interesting experiences you’ve had creating new versions of your software when OS is upgraded?

WM: An OS update always makes developers a little jittery, but so far everything has gone smoothly. I was able to plug directly into a number of Objective-C 2.0 features that came about it Leopard, and that made the development of Deductions a lot easier. I have no doubt that we’ll be incorporating some Snow Leopard technologies into Deductions too. I’m thinking about putting the hint engine into a separate thread using Grand Central Dispatch.

Q: What features would you like to add to your product that at this time seem improbable/impossible?

WM: I’d really like to improve the hint engine to the point that it gives advice several steps ahead: not just “derive a contradiction,” but “derive this particular contradiction in order to achieve this particular goal.” Now for really fascinating reasons (to me, anyway) that have to do with the computability of predicate logic, there are fixed limits on just how far advice can go. But I’d love to do the research necessary to design a hint engine that presses right up against those fixed limits. That just seems out of reach right now.

Q: What should a beginning logic student know before purchasing Deductions?

WM: If you are taking a class, you should know that formal logic is unlike mathematics in that the symbols and rules differ from textbook to textbook. Deductions works with several popular textbooks, and is very configurable, but it does not work with every textbook. If your textbook is The Logic Book by Bergmann, Moor and Nelson, A Modern Formal Logic Primer by Teller, or An Accessible Introduction to Serious Mathematical Logic by Roy, then Deductions will be of great help. If you are using some other textbook, Deductions may or may not be compatible; feel free to contact us if you’re not sure, or ask your instructor.

Q: Can someone use Deductions even if not taking a logic course?

WM: Of course! Deductions has several video tutorials that you can follow, but if you really want to learn how to do proofs in formal logic, you’ll want to follow a textbook or set of lectures. Fortunately, Teller’s Modern Formal Logic Primer and Roy’s Accessible Introduction to Serious Mathematical Logic are freely available on the web.

Q: What’s your favorite Mac app out there from another developer? Why?

WM: VoodooPad, without a doubt. I use it to keep track of notes, press releases, marketing, feature requests and business expenses. I use it to write the Deductions help files. I find it indispensable.

Q: Can you us more about your company?

WM: I started Wandering Mango just this year, and Deductions is my first product. I’m hoping to make a go of it as a Mac indie developer. I think I’m lucky in that the market for Deductions is pretty well-defined (instructors and students who study formal logic in philosophy, mathematics, and computer science, and other people interested in formal logic).

Q: What’s with the name “Wandering Mango”?

WM: Well, Mac indie developers tend to have incongruous names that stick in your head: Rogue Amoeba, Flying Meat, Delicious Monster, and so on. Our name follows that tradition. A friend of mine decided that “Wandering Mango” sounded like a drink, and she created a recipe to celebrate our first app. It’s on our About page, and it’s really very tasty.