<P> The continuity and difference between Descartes' and Aristotle's conceptions is noteworthy . In both conceptions, matter is passive or inert . In the respective conceptions matter has different relationships to intelligence . For Aristotle, matter and intelligence (form) exist together in an interdependent relationship, whereas for Descartes, matter and intelligence (mind) are definitionally opposed, independent substances . </P> <P> Descartes' justification for restricting the inherent qualities of matter to extension is its permanence, but his real criterion is not permanence (which equally applied to color and resistance), but his desire to use geometry to explain all material properties . Like Descartes, Hobbes, Boyle, and Locke argued that the inherent properties of bodies were limited to extension, and that so - called secondary qualities, like color, were only products of human perception . </P> <P> Isaac Newton (1643--1727) inherited Descartes' mechanical conception of matter . In the third of his "Rules of Reasoning in Philosophy", Newton lists the universal qualities of matter as "extension, hardness, impenetrability, mobility, and inertia". Similarly in Optics he conjectures that God created matter as "solid, massy, hard, impenetrable, movable particles", which were "...even so very hard as never to wear or break in pieces". The "primary" properties of matter were amenable to mathematical description, unlike "secondary" qualities such as color or taste . Like Descartes, Newton rejected the essential nature of secondary qualities . </P> <P> Newton developed Descartes' notion of matter by restoring to matter intrinsic properties in addition to extension (at least on a limited basis), such as mass . Newton's use of gravitational force, which worked "at a distance", effectively repudiated Descartes' mechanics, in which interactions happened exclusively by contact . </P>

8 letter word that would define all materials on earth