Tosfos Bobo Kamo 2a - Tosfos.com

And R’ M’nachem explained that the G’moro means to say as follows:
An animal that is muod for people, who was a muod for everything
including animals, and he retracted from animals, he saw an animal
three times and did not attack it, but he remained a muod for people, there
was no evidence that he retracted from killing people, remains a muod for
animals, for the retraction from killing animals is inconclusive, as long
as he remains a muad for people.
However, a muod for everything, people and animals, who retracted
from killing people, is no longer muod to kill people, for his retraction
from killing people is a retraction. According to this answer as well, we
see that an animal is more likely to kill animals than humans, therefore his
retraction from killing animals is inconclusive as long as he remains muad
for people, but his retraction from killing people is a retraction even though
he remains a muad for killing animals.
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