(Information provided by Mr. Weintraub)

See also Weintraub's Website


First program to win the Loebner Prize

The first PC Therapist program was written in 1986. Joseph Weintraub, the author, had graduated with a degree in Psychology, and then immediately become a Mainframe Computer Programmer. The frustrated therapist in him spilled out into the program, and gave the PC Therapist it's Woody Allen type humour and helpful tone.

He wrote the Therapist shortly after buying and returning the most famous Artificial Intelligence program, ELIZA. Eliza is a simple but clever program that mimics a Rogerian Therapist by turning your own words and phrases back at you. If you say "I need my Mommy", ELIZA will say "Tell me why you need your Mommy?" However, ELIZA has no knowledgebase and nothing of its own to talk about.

Weintraub was bored with the ELIZA program after ten minutes, and infuriated that he had spent so much money on it. He was sure he could write a better talking software program. He spent several days planning the program and then got to work on the first version of The PC Therapist. Many all nighters at the keyboard soon followed.

He founded Thinking Software in September of 1986 to market the resulting program, which sold consistently at the original price of $29.95. Users were generally pleased. One typical letter said "Thanks so much for the program. I find it to be a witty and amusing companion, and much to my amazement, theraputic!".

The program was continuously being improved, and had a knowledgbase that grew as you talked to the Therapist, absorbing most of what you typed. A year later, a version was written that included Speech Synthesis using the Creative Labs SoundBlaster, which produces very clear and understandable human speech.

Creative Labs featured The PC Therapist in their annual Newsletter:


"We are always intrigued with third-party software titles that support the SoundBlaster. This one however, takes into account several advanced technologies that are amazing!"

"The Talking PC Therapist from Thinking Software, Inc Woodside, N.Y. is an Artificial Intelligence program which demonstrates Natural Language processing, speech synthesis, and machine learning on any PC or compatible. It employs AI sentence parsing and knowledebase technology, plus a 70,000 word vocabulary. The Therapist learns everything that is said to him, so conversational ability constantly grows. After a few sessions, the therapist gets to know you quite well. Type in anything....your most intimate secrets, desires, wants, emotions...or vent your anger and hostility. The Therapist always responds with a cool, calm, and often humorous reply."

"For the first time, you can have a long satisfying conversation with your PC."

The Turing Test

In 1950, Alan Turing proposed the Turing Test as a way to determine if a computer program could think like a human being. He proposed that a judge talk to a computer and man over telephone lines, and see, if by conversation alone, he could choose the human. If he was "fooled" by the computer program, then it was truly Artificially Intelligent.

The Loebner Prize

On November 8, 1991, the first Turing Test in the world was held at the Boston Computer Museum on a grand scale. Among the participants were eight computer programs talking through modems, and two human confederates also at remote locations.

The judges had only a terminal number (1 to 10) and a topic printed on a card affixed to the terminal. Some of the topics were: Whimsical Conversation, a dry martini, Shakespeare, romantic affairs. Whimsical Conversation was a "nom de plume" suggested by Dr. Robert Epstein, one of the organizers of the event.

Five of the ten judges decided that Whimsical Converation was human. In reality, it was the PC Therapist III from Thinking Software in Woodside, New York running on a Northgate 386 PC. It was a landslide win!

The PC Therapist III: technology

The PC Therapist III is made up of seven modules written in C, Turbo Prolog and QuickBasic. The Main Module reads the input sentence, calls a Prolog Module for parsing, and based on the content of the sentence, either uses portions of it in a reply, or accesses a half-megabyte knowledgebase called KBASEK for a relevant quote or phrase. There is also a short-term memory, a module that tracks the current topic, and a grammer module. The PC Therapist learns everything that is said to it, so conversational ability is always increasing.

One of the useful features of The PC Therapist III is that your entire conversation is stored in the file REPORT.TXT. This makes the program extremely useful for writers, reporters and students. When you find you have writer's block on a particular topic, just chat with the PC Therapist about it for an hour. Then import the resulting ASCII Text File REPORT.TXT into your favorite word processor. You can delete the Therapist's part of the conversation, or use it if you prefer.

The PC Therapist IV

The PC Therapist IV is aimed at kids and teenagers. It adds a cute animated Talking Head and Voice Synthesis thru the PC Speaker. He is a lot more fun for young people to chat with, and would be useful to enliven a party.

He will also help young children learn to type, and to get friendly with the computer and the keyboard.

He can also, amazingly enough, be used to teach a child about a particular topic. Rename KBASEK to another name. Type in 50 or one hundred sentences about the topic you want to teach the child, ignoring anything the PC Therapist says. He will grow a new KBASEK devoted solely to your new topic, and will now be a suitable teacher on that new topic the next time he is used.

Ordering Information

The PC Therapist is available for all IBM/PC's and compatibles, including the AT 286, the 386, and the 486. There are no special hardware requirements, but a hard drive and color monitor improves performance. DOS 3.1 or later is required. Shipping is by First Class or Airmail only.

The PC Therapist III is the EXACT PROGRAM that won the Loebner Prize at the Boston Computer Museum on November 8th, 1991. It is a purely text based program, and is $59.95 plus $5 Shipping/Handling.

The PC Therapist IV adds a Talking Head and Voice Synthesis through the standard PC Speaker. It is $64.95 plus $5 Shipping/Handling. Kids and teenagers will prefer this version with the little onscreen talking head. The SoundBlaster Version is $69.95 and features quality stereo sound.

PC Professor - discusses Men versus Women - winner 1992 Loebner Prize $69

PC Politican - discusses Liberals versus Conservatives - winner 1993 Loebner Prize - $99

Send your check or Money Order to Thinking Software, 46-16 65th Place, Woodside, N.Y. 11377. We take credit cards, but no CODs A U.S. Postal Money or International M.O. or Credit Card is advised for overseas orders. Overseas Airmail add $10. Email (Credit card orders Only) LVNF51A@prodigy.com