Thoughts and stones have something in common. A sad thought can fall on us as heavy as a stone, and a meteorite can cross the sky as quick as a thought. But apart from these metaphorical associations, a further relation between the ideal and the material world can be traced. In the late seventeenth and early eighteenth centuries, Gottfried Leibniz argued that a “[…] body has a degree of hardness as well as a degree of fluidity [… and] it is essentially elastic, the elastic force of bodies being the expression of the active compressive force exerted on matter” (Deleuze 2006, 6). Reading Leibniz’s philosophical writings, we find out that elasticity is also a requisite of thought, the pliable material of the mind (or, in Leibnizian terms, of the ‘soul’), “because the body and the soul have no point in being inseparable, for they are not in the least really distinct” (13). In other words, the matter of which (we think) bodies (such as stones) are composed and also, by extension, the matter of thought, unravels itself as elastic drapery. Reflections and actions can both be imagined as topological operations of dilatation and compression, distension and contraction, stretching and tightening of some elastic matter-thought: in order to develop an idea or to chisel a block of stone, one always has to unfold and re-fold the molecular intricacies of an extremely compressed, but also infinitely extensible, material. If matter-thought is the elastic fabric of the world, the fold is its main creative event.