A central flaw in the argument linking vaccines to autism is the logical error of assuming causation from correlation. The original controversial study reported that some children developed autism symptoms shortly after receiving the MMR vaccine. However, this temporal sequence is merely a correlation—two events happening around the same time—and does not prove that the vaccine caused autism. This is a classic example of the 'post hoc ergo propter hoc' fallacy, especially since the typical age for autism diagnosis coincides with the childhood vaccination schedule.