Spontaneous generation is the scientific fallacy
that holds that some forms of life
arise spontaneously from non-living matter. This generation was observed primarily in decaying
matter, for example, a slab of dead meat would give rise to maggot
s. Or take a seventeenth century
recipe for the spontaneous production of mice
: place sweaty underwear and husks of wheat in an open-mouthed jar, then wait for about 21 days, and the sweat from the underwear will turn the husks of wheat into mice. The invention of the microscope only strengthened this theory, as a whole world of "animacules" could now be observed to arise from, for example, hay left in water.
The theory of spontaneous generation was put to death by experiments by Francesco Redi
, Lazzaro Spallanzani
, and Louis Pasteur
, in the 17th through 19th centuries.