  Gassendi introduces notions of absolute space and time according to which the universe is that which contains material Creation. In the colloquial language of metaphysics, he lays out the ‘floor plan’ of his picture of the universe in which he understands God to place the ‘furniture’, namely, atoms and their amalgams.  Space, time, accident, and substance are the basic and real (non-ideal) categories of existence: space and time are not modes of substance (see section ten). ‘Matter’ refers to substance that exists in space and time. Indeed, it is the sole and unchanging stuff of physical things and so must exist as long as physical things exist. Gassendi wants bits of matter to have their distinctive qualities without the scholastic imposition of form. In particular, he proposes, matter has essential and accidental qualities, though we can only know the accidental ones, through experience.