The paper is an attempt at a logical justification of the theological dogma concerning the incomprehensibility of angelic intelect for human minds. Descartes’ concept of mind, which is constituted by its own thinking, excludes the possibility of interlocutor and of any relations to the material objects. The thinking of an isolated mind is necessarily of a solipsistic nature, having no independent means for the verification of the regularity of the rule-governed applications of concept. To eliminate the solipsism stemming from private rules the condition of the public, intersubjective discourse allowing for the adjustment and correction of rules of speech has to be introduced. The condition of intersubjectivity alone is not sufficient to establish the regular speech. An external, systematically ordered network of material objects allowing for the unique descriptions and refferences is needed. The pre-predicative facticity of the material world and the biological make-up of the species Homo Sapiens are among the logical presuppositions of an intelligible language. Cartesian and angelic minds, lacking human phenomenology of experience, are from human point of view primarily incomprehensible. This seems to support the doctrine of the Great Chain of Beings and to require the elimination of Cartesian-like models of human mind in social sciences.