Published online by Cambridge University Press: 29 July 2016
It is well known that in the Middle Ages mathematics had little part in the study of nature. Natural philosophy, which had in its purview all of nature and natural things, was considered fundamentally distinct from mathematics, both in subject matter and in method. Yet there was a handful of sciences in which mathematics and natural philosophy came together, sciences that were to have a very significant role in later scientific thought. These were what Thomas Aquinas, in the thirteenth century, called the ‘intermediate sciences’ (scientiae mediae), since they were thought of as in some way intermediate between the natural and the mathematical; they included astronomy, optics, harmonics, and sometimes mechanics. They were also known as the ‘subalternate sciences,’ since they were considered under, or subalternate to, pure mathematics, and sometimes to natural philosophy as well.
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36 ‘Et hec propositio secundum quod est simpliciter geometrica abstrahit a triangulis et ab angulis et a lateribus radiosis et non radiosis, sed secundum quod venit in sillogismum demonstrantem conclusionem predictam speculative appropriatur ad triangulos et angulos et latera radiosa hoc modo: omnium duorum triangulorum radiosorum, quorum unus angulus radiosus unius est equalis uni angulo radioso alterius et latera radiosa equos angulos radiosos continentia proportionalia, reliqui anguli radiosi prout se respiciunt sunt equales’ (Comm. Post. Anal. 1.8 [ed. Rossi, , p. 149.72–80]).Google Scholar
37 ‘Sed omnes duo anguli, quorum alterum constituit radius incidens cum speculo et reliquum radius reflexus, sunt duo anguli radiosi sese respicientes duorum triangulorum radiosorum quorum unus angulus radiosus unius est equalis uni angulo radioso alterius et latera radiosa equos angulos radiosos continentia proportionalia…’ ( Comm. Post. Anal. 1.8 [ed. Rossi, , p. 149.80–84]).Google Scholar
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