If you're trying to cite Koch's postulates, you probably have run into researchers applying them to VIRUSES, not poisons. I think you're confusing those two things. The original definition of "Virus" is "poison or venom," so that might be the trouble. Poisons definitely exist, but no virus (DNA strand with a sheath, or the spiky ball that invades cells and cause disease) has ever been isolated; they are a fabrication.
If you're trying to cite Koch's postulates, you probably have run into researchers applying them to VIRUSES, not poisons. I think you're confusing those two things. The original definition of "Virus" is "poison or venom," so that might be the trouble. Poisons definitely exist, but no virus (DNA strand with a sheath, or the spiky ball that invades cells and cause disease) has ever been isolated; they are a fabrication.
Can you tell me why satisfying some dudes assumptions is a scientific requirement at all?
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