Just as the light of the sun irradiates the organ of vision and things visible, enabling the former to see and the latter to be seen, so too the irra… - Robert Grosseteste

The consideration of lines, angles and figures is of the greatest utility since it is impossible for natural philosophy to be known without them... All causes of natural effects have to be given through lines, angles and figures, for otherwise it is impossible for the reason why (propter quid) to be known in them.

The diligent investigator of natural phenomena can give the causes of all natural effects... by the rules and roots and foundations given from the power of geometry.

In a vacuum which is imagined as infinite there cannot be local differences, both on account of its infinity, and also because of the fact that the vacuum, if it exists, would have no nature but a privation, and therefore it can have no natural differences.