The guillotine was named after Joseph Ignace Guillotin, a French doctor and politician. But he did not invent the execution device that later carried his name.
In 1789, Guillotin argued that if France was going to keep capital punishment, it should use a method that was the same for everyone. At the time, execution methods could vary by social class and by the crime. He supported a machine based method because he believed it would be quicker and less painful.
The actual design is usually linked to other figures, including the surgeon Antoine Louis and the maker Tobias Schmidt. Early on, the machine was even called the Louisette or Louison, after Louis.
- Guillotin: proposed the idea in public debate.
- Antoine Louis: helped develop the design.
- Tobias Schmidt: built an early version.
So the famous name comes from the man who advocated for the reform, not from the people who actually designed and constructed the machine.