The *[[nLab:Cahiers topos]]* is the sheaf topos on the [[nLab:site]] [[nLab:CartSp|ThCartSp]] of *infinitessimally thickened cartesian spaces*. More generally the *[[nLab:synthetic differential infinity-groupoid|higher cahiers topos]]* is the $(\infty,1)$-sheaf $(\infty,1)$-topos on the $(\infty,1)$-site [[nLab:CartSp|ThCartSp]]. However the $(\infty,1)$-topos arising in this way is (still) a [[nLab:n-localic (infinity,1)-topos|1-localic]] (i.e. [[nLab:localic topos|localic]]) $(\infty,1)$-topos; in other words this notion of *higher cahiers topos* is no more intelligible than just the classical cahiers topos. ## References * Jacob Lurie, [[nLab:Formal moduli problems]] * Vladimir Hinich, DG coalgebras as formal stacks, ([arXiv:math/9812034](http://arxiv.org/abs/math/9812034)