The article presents a theme of reconstruction of the polemic between analytic philosophers and psychologists concerning the relations of thought, language and speech in expression of private experiences. The method of comparative analysis helped the author to elaborate L. Wittgenstein’s argument for reduction of cogitative operations to language, and language to logical propositions. Expression of individual experiences becomes aRb justified because of their transfer to forms of attributive kind. This procedure complicated the congruence of form and content of private experiences in speech. The alternative point of view presented by psychological ideas by J. Piaget and L. Vygotsky, as well as their contemporary expounders, provides the extended interpretation of mind considering its development across the lifespan. Types of speech, namely the external speech and the inner speech, were distinguished. The external speech showed the direct link with thought and logical forms of language to express private experiences. The inner speech disclosed opportunities to express private experiences via connection of thought with language mediated by imagination. In social-cultural regard, the inner speech becomes the channel for translation of private experiences by imposing impulses created by the person on performative forms of the statement (were disclosed in the Theory of Speech Acts by J. Austin). The novelty of the research is contained in the introduction of the modern forms of Unity-Variety dialectics, correlated to the polemic on the nature of human mind and channels for translation of private experiences. In psychology, the result opens prospects to analysis of mind structures, which mediate thought and language in expression of private experiences.