Robotics Reference
In-Depth Information
1903), Macaulay (in 1910) and Shchukarev (in 1914), were designed
to prove conclusions from a given set of premises. But none of these
machines could discover fallacies in a deductive process. Burack's ma-
chine was therefore unique in two distinct ways—it was the first electro-
mechanical logic machine to be built and the first logic machine of any
sort that could demonstrate fallacies in logical arguments.
Burack's machine was mounted inside the top half of a sturdy suitcase
and weighed about 25 pounds. Burack used a flat wooden block to rep-
resent each logical statement (the premises and the conclusion). In order
to test the validity of reasoning of a syllogism, Burack would select the
blocks representing each of the premises and the conclusion, and place
these blocks onto three spaces provided on the panel of the machine. If
the proof contained one or more fallacies, i.e., if it was not a valid proof,
one or more light bulbs would be illuminated. Each of the light bulbs
indicated a different type of logical error in the proof, making it easier to
trace the fallacy.
The machine operated by establishing metal contact areas on the
backs of the blocks, to convey to the machine information concerning
the statement printed on the front of the block. For example, the block
representing “Some M is not S” (which could be employed in “some cats
are not black” or any similar statement), had separate contact areas on
the back of the block to represent information about the statement. One
of these items of information on this particular block was that the state-
ment is negative (because of the logical operator
not
); another was that
the statement refers to “some” rather than “all” or “none”.
When the blocks were set into the front panel of Burack's machine,
the metal contact areas on the backs of the blocks were connected to
plugs in the panel. Certain combinations of blocks would close one or
more of the electrical circuits that were wired from the panel to the bulbs.
When a fallacy was detected, the appropriate bulb would be illuminated.
Claude Shannon and Electrical Logic
Claude Shannon (1916-2001) came from a fairly well-educated family
and his early environment was one of intellectual stimulation. In fact,
he spent much of his youth working with radio kits and Morse code.
In 1938, while a graduate student at MIT, Shannon published his mas-
ter's thesis, which became a seminal paper on the application of symbolic
logic to relay circuits. He showed that the TRUE and FALSE aspects
