Answer
It seemed logical to them because they did not understand the underlying causes for those things (maggot eggs being laid on the meat, etc.). They did not understand that those animals/insects were always coming from outside sources to feed on the meat. If they would have performed a controlled experiment in which they kept grain in a container that outside mice could not get into, or prepared and kept meat in a place that flies could not reach, they would have understood that spontaneous generation was wrong. Keep in mind, back then there was no such thing as sterile conditions, or tupperware, or refrigerators. Insects and bacteria pretty much ran around rampant, so the people living during this time probably never saw a piece of meat that didn't eventually become covered in maggots.
Work Step by Step
It seemed logical to them because they did not understand the underlying causes for those things (maggot eggs being laid on the meat, etc.). They did not understand that those animals/insects were always coming from outside sources to feed on the meat. If they would have performed a controlled experiment in which they kept grain in a container that outside mice could not get into, or prepared and kept meat in a place that flies could not reach, they would have understood that spontaneous generation was wrong. Keep in mind, back then there was no such thing as sterile conditions, or tupperware, or refrigerators. Insects and bacteria pretty much ran around rampant, so the people living during this time probably never saw a piece of meat that didn't eventually become covered in maggots.
