By Schubert Ogden
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According to one traditional scheme, there are two "ways," or a "twofold way" (= duplex via) along which scientific activity proceeds:
1. There is the via inventionis (= way of invention or discovery), which proceeds from how things seem to be, from the prius quoad nos to the prius quoad se.
2. There is the via disciplinae (= way of the discipline or exposition and confession), which proceeds from how things are in themselves, from the prius quoad se, to the prius quoad nos.
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