Guide to the Logic software:

General Information:

Assignments are to be done via the UCLA Logic 2000 software program. In my experience with this program, it has always proven to be a very helpful resource for students. This will demand of you, the student, some energy and effort early in the term, to learn your way around the program. Once you have done that, you will reap many benefits over the course of the term. The program will be there to help you out, whenever you want it. It takes away a lot of the frustration that can be caused by first encounters with difficult logical problems, it steers students clear of many common pitfalls, and it just makes learning logic less arduous and more enjoyable.

The software is installed on the PCs in the computer labs CP-2003 and CP-2004, and in some but not all of the PCs in the Commons in QE2 Library. (It is for sure installed on the 20 or so machines in the back hallway; and I was promised that it will be installed on all Commons machines.) To use these labs, one needs a PCG Labs Account, which can be set up by visiting the Commons in QE2 Library.

Anyone who so desires can download the software onto their own PC. Connection to the internet is required to download the software, to start a work session, and to submit completed work. (It is not necessary to be connected to the internet throughout the work session. So, those dialing in from home can dial in to get hooked up, then remain undialed while working on the assignment, then dial in again to submit the work.) The software is available at:

http://logic2k.humnet.ucla.edu/download.html

Some Tips:

Students may use some combination of the above two options (e.g., do an hour’s work at CP-2004 during the day, and another hour’s work from home in the evening), even during one given assignment. As long as you follow the instructions for Saving and Backing-up your work, it is all saved for you out there in cyber-space (on UCLA’s logic database).

It is NOT necessary BOTH to get a PCG Labs account for work in the CP labs AND to download the software onto your own PC. However, all students must do at least one of them; and most students find it useful to do both.
The UCLA logic portal at

http://logic2k.humnet.ucla.edu/LogicStudent.cfm is a helpful resource that it is worthwhile to bookmark.

Getting with the program

If your first session with the logic software is at the CP lab, then you start by clicking ‘Start’, then ‘Programs’, then ‘Philosophy 2210’, and finally the ‘Logic2K’ icon. If you begin on your own computer, your first step is to get online, get to the above website, and follow the instructions. Either way, once you are up and running just follow the instructions for setting up a Logic account. You will be asked for your student ID, name, email address, etc. Nb:Be careful to select ‘Fall 2008’ when asked to choose the term.

Then you are in, and the main menu pops up. On top it says:

Logic 2000: A Workbook

Under this it says: “Please choose a module”. What follows are 16 modules, divided into 3 groups. This is the menu, the center and jumping-off place for all modules. It is also the only place from which you can backup your work and exit the program.

Top Group: Kinds of exercises

The top group contains the six options: Derivations, Invalidity, Parsing, Recognizing Rules, Symbolization, and Truth tables. These are the six types of exercises in the program. Your assignments will consist of problems drawn from these six modules. For more info on these modules, see ‘a bit more on what to expect’ below.

Middle Group: Helpful references

The middle group contains three options: Using Logic 2000, About Logic 2000, and Menu Help. These are three helpful resources you might want to have a look at, containing information about the program and how it works. (Students are particularly advised to print a copy of ‘Using Logic 2000’, and to keep it on hand for reference while working on assignments.)

Bottom Group: Administrative options

The bottom group consists of seven administrative options:

• ‘Assignments’ takes you to the webpage:

http://logic2k.humnet.ucla.edu/LogicStudent.cfm.

Here you can view the status of all the work you have submitted, to date. (It is a good idea to check here, when exiting the program after doing some work, to be sure that your work has been successfully submitted.)

• ‘Course website’ takes you to the course homepage.
• ‘User information’ lets you know exactly who is currently logged onto the machine at which you sit. This is important at the labs, or on any computer on which more than one person will be doing assignments. Check here to make sure that someone else won’t get the credit for the work you do.
• ‘Backup’ saves your work and submits it to the UCLA logic database. Always always always backup before ending your work session. As long as you do this consistently, you can access your work-files from any on-line computer. (This takes at least a few seconds, and could take up to a minute, depending on traffic at the time.)

• ‘Copy’ allows you to copy the work onto a floppy disk. This was important for previous versions of the program, it will not be that useful for us this term. (If you ‘backup’ regularly, you should have no need for ‘copy’.)

• ‘Delete work/quit’erases the temporary work-file on the computer at which you sit, and then exits the program. This is the option you’d use at the labs, or on any computer at which more than one person is doing assignments.

• ‘Quit’ just quits. If you use this one, your work files will be automatically called up next time the Logic program is opened. This is appropriate on your own private personal computer, but it will (slightly) inconvenience the next Logic user if you do it in the labs.

*ALWAYS ALWAYS ALWAYS ‘Backup’ before ‘Quitting’!!! If you are using a computer at which more than one person is doing the assignments, then first backup, then delete/quit. If you are using your own private machine, then first backup, then quit.

A bit more on what to expect:

The assignments will consist exclusively of six sorts of problems. The two most basic are: [1] Parsing – identifying what is and is not a well-formed expression, and [2] Recognizing Rules – identifying what is and is not a valid application of a rule of inference. The aim of these exercises is to help the student to master the basic bits of the logical language. One cannot go any further without mastering this stuff, but these problems are too elementary to appear on a test or exam.

Next in order of complexity is [3] Symbolization exercises – formalizing sentences and arguments from English into logical notation. This is a crucial skill for symbolic logic, and so Symbolization exercises make up a significant portion (i.e., roughly a third) of each test and exam.

[4] Derivation exercises – developing ways to prove that an argument is valid – will be the largest component of the student’s total assignment workload, over the term, and also the largest component of each test and exam. This is what logic is all about.

Finally, [5] Truth tables (introduced in Chpt.2) and [6] Invalidity (introduced in Chpt.3) develop ways of proving that an argument is invalid. Truth table exercises will appear on Test #2 and the Final Exam, and Invalidity exercises will appear on the Final.

*Within each of these six modules, upon first opening the module up, one is faced with a blank screen with a number of buttons along the bottom. Here is an explanation of what these buttons do (cut-and-pasted from the aforementioned ‘Using Logic 2000’ file):

Button
Function
Select

(Select Problem)
Used to select a problem to work on. You may select one of the preset exercises or a User problem that you have already saved.

User
(User Problem)
Used to create a “User Problem”, a new problem of your own that is not in the list of exercises.

Rules*
(Display Rules)
Pops up a window showing all the inference rules. For derived rules, the theorems necessary to derive the rule are indicated.
Direct**

(Direct Entry)
Opens a window into which the symbolization can be entered directly without building a tree.

Check
Initiates an automated check of your work on the current problem, and displays messages describing any errors.

Save
Saves your work on the current problem to the “Logic” work-folder on your local hard disk, where it will be available to be recalled for editing or printing or submitting. Whenever you leave a module you will be prompted to save any unsaved work.

Delete
Pops up a window asking if you wish to delete the work on the current problem (and begin anew). If the problem is a User problem, you also have the option of deleting the problem itself.

Submit
Submit one or several problems across the Internet to the course database. After clicking the Submit button, you will verify your course, instructor, and TA, and then enter your logic password, and select the exercises you wish to submit, using Ctrl+Click. Click “Submit” at the bottom of the selection window to submit all of the selected problems. After a brief delay, you will receive an acknowledgment that the work has been successfully received. If not, try again.

Print
Pops up the Print window, which lists all of the preset exercises along with all of the User problems that you have saved. The current problem will be highlighted. Use Ctrl+Click to select (or deselect) more than one exercise to print. The Print button at the bottom will then initiate printing of your work, one problem per page. You may also choose the Print Results button, which causes a single page to be printed showing just a list of the selected problems with the results of your work (Correct or Incorrect), but without showing the work itself. You can also print a list of the exercises by first highlighting them and then clicking the Print List button.

Menu
Summon the Menu window.

Close
Close the module window. You will be asked if you wish to save any unsaved current work before the window is closed.

Feedback
Send anonymous (or open) suggestions about the program or any aspect of the cou rse to the program developers, the instructor, and TAs. Another source for questions and comments is the Discussion Board on the course website. The course website can be accessed from the Menu.

Help
Read a full explanation of how the given module works.

FAQ*
Read the answers to Frequently Asked Questions.

Advice*
Get help with strategies for constructing derivations.

Examples**
Read examples and explanations of symbolization problems.

References***
In the Recognizing Rules module read a discussion of the primitive and derived rules of Chapters II and III. In the Truth Table module, view the defining tables for the sentential connectives.

 

<sub>*Derivations module only.
**Symbolization module only.
***At present, Recognizing Rules and Truth Tables module only.
‘Select’ is the first button you’d hit, in starting work on an assignment. This brings up a list of problems, from which the assignments will be drawn. Just click on a problem to get into it.
Note that after you have successfully completed a problem, it occurs in green on the Select list. If you have worked on a problem but not successfully completed it, it occurs in red on the Select list. (In some modules, some problems already are already green- or red-lighted, even the first time you encounter them. These are problems that are already done, for illustration, by the program’s designers. Those green-lighted are done correctly, to show you what to do; those red-lighted are done incorrectly, to illustrate some common errors.)
‘Help’ is also a very important function, as it tells you what to do and how to do it, within each module. At least in the early stages, you will probably be going to this key often. It might be a good idea to print these Help documents, and keep them on hand as resources.
‘Check’ and ‘Save' are other crucial keys. You have to press Check to find out whether you've gotten things right. If not, the program will advise you as to what’s gone wrong. Once you’ve corrected things, and it Checks out correctly, you have to Save the problem, then move on to the next one. (When printing or submitting work, it is the last saved version that gets printed/submitted.)
One last helpful tip concerns the ‘Toolbox’. Within any module, if you right-click the mouse, a toolbox of symbols and keystrokes appears. The contents of the toolbox vary from module to module. You are never required to use the toolbox; it just helps to save time, on a lot of problems – particularly Derivations and Symbolizations.
Submitting Assignments
Save and Backup are important steps in the process of completing an assignment, but they are not enough. You have to Submit your work as well. The safe but slow option is to Submit every problem individually (after it Checks out correctly and you’ve Saved it). The slightly more advanced, quicker option is to Submit many problems at once (using the ‘control-click’ function mentioned in the above table).
*‘Save’ saves the selected work into the currently open temporary work-file on the hard-drive of the computer at which you sit
*‘Backup’ saves the selected work on the UCLA database, from which it can be accessed via any on-line computer.‘Backup’ will be especially crucial in Ch’s 2-3, when having a cumulative record of work completed becomes an enormous time-saver. It is a good habit to get into, after every work session.
*‘Submit’ saves the selected work to our course database. To Submit work is to hand it in: You must Submit your work, in order to get credit for it.
* The ‘Assignments’ module (one of the Administrative options on the bottom part of the Menu) lets you view what you have Submitted. It is a good idea to check this out, before exiting the program, to be sure that your work has been successfully Submitted. Individual student work-files can also be accessed directly over the internet at: http://logic2k.humnet.ucla.edu/LogicStudent.cfm</sub>