Hello Oppress,
I believe the positive 'nature' of current flow is attributed to Benjamin
Franklin, whose scientific ideas were apparently better known than his political
ones for a time in Europe. I understand that it is purely a matter of
convention, I emphasize this with my students so that they get a flavor for what
humans do when trying to understand nature. I hope this helps.
Fernando Espinoza
Science Education, Lehman College, New York, USA
Physics and Astronomy, Hofstra University
Hempstead, New York, USA

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