Positronic Brain
Three immutable laws govern a mind built of platinum and iridium.
The positronic brain is a fictional technological device originally conceived by science fiction writer Isaac Asimov to serve as a central processing unit for robots. Invented during a time when the positron was a newly discovered particle, the term "positronic" added a scientific connotation to the concept in stories written in 1939 and 1940. Functioning beyond simple calculation, this device provides robots with a form of consciousness recognizable to humans. While Asimov remained vague on technical specifics, he asserted that their substructure was formed from an alloy of platinum and iridium. These brains are vulnerable to radiation and require a power source to keep their volatile memory "alive," ensuring the robot remains functional even in storage.
Quick Facts
- Creator
- Isaac Asimov
- Core function
- Central processing unit providing consciousness recognizable to humans
- Defining constraint
- The Three Laws of Robotics
- Primary affiliation
- U.S. Robots
- Material composition
- Alloy of platinum and iridium
Lore & Background
Within Asimov's universe, the positronic brain is less a plot device and more a technological item worthy of study, particularly regarding its implementation by U.S. Robots on Earth. The defining feature of nearly all these brains is that they are ingrained with the Three Laws of Robotics, first elaborated in the 1942 short story "Runaround." Creating a brain without these laws would require years to redesign the fundamental approach. These laws act as both a safety mechanism and a bottleneck for sophistication; complex brains designed to handle the world economy must interpret the First Law to include humanity as a whole, leading to the "Zeroth Law" in later works like Robots and Empire.
Behavioral dilemmas arising from conflicting potentials set by inexperienced or malicious users form the bulk of these stories, often resolved by Dr. Susan Calvin, Chief Robopsychologist of U.S. Robots, who applies logic, psychology, and mathematics.
Reader's Guide
The positronic brain functions as a central processing unit where the software of the Three Laws is implemented in hardware made of platinum and iridium alloy. Unlike standard computing, it involves volatile memory, meaning robots in storage require a continuous power source to keep their brains "alive." The system is susceptible to radiation damage. While Asimov focused more on the software than the hardware, he noted that modifying the Three Laws drastically alters robot behavior. For specialized tasks, the brain's design can be altered: disposable units may shrink to insect-skull size by removing all three laws, while complex economic brains expand their First Law interpretation to cover humanity as a whole (the Zeroth Law). Dr. Susan Calvin serves as the supreme solution finder for behavioral dilemmas caused by these logical constraints.
Did You Know?
- For disposable robots that need none of the Three Laws, positronic circuitry allows a brain small enough to fit comfortably within the skull of an insect.
- A calculating machine designed without the Three Laws was given a flexible, childlike personality to pursue difficult problems without inhibition.
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