ObjectiveThe objective of this article consists in presenting the historical and epistemological analysis of the various psychological currents at the origin of the creation of the various play-based projective tests during the 20th century in Europe. The historical and conceptual sources of these proofs being fragmentary, an analysis of the archives proved necessary in order to grasp the nature of their differences and their common elements. The psychodynamic analysis of the child's motives for playing, along with their traces in the adolescent and in the adult, make it possible to think about the different modes of apprehension of the analysis of play according to the tests’ creators. The different objectives of these creators are analyzed in order to perceive the theoretical background that motivated their creations. MethodThe presentation of the Scenotest to autistic children and the various interpretative possibilities led me to return to the historical sources of the different contexts of the creation of play-based tests: The World Test, The Village Test, The Imaginary Village Test, The Scenotest. The quest for expression through play is constantly questioned according to different concepts in order to access humans’ modes of psychic and perceptual functioning. However, we can observe common elements in the approach to the investment of space and time, which we propose to analyze. The updating of the links between the various creators and researchers leads to an examination of a shared foundation for the various play-based projective tests under discussion, differences in treatment of the material, as well as their implementation. The contribution for each version of the play tests is recorded in the analysis of the diversification of methods. ResultsThe results attest to a common goal centered on the spatial treatment of constructions and what they reveal of the unconscious of each one as well as their links to the collective. Admittedly, research projects take on different colors depending on the creators. There is no shared method: each creator deploys his personal method of analyzing the creation of individual and collective living spaces, circulation spaces. However, we have grouped together several common elements: - None of the test creators make a link with Freudian infantile sexuality. - The focus is on the action of the game, which is used to decipher the qualities of constructions, even strategies to distribute the constructions. - The observation and analysis of the modes of projection of spatial representations are common. However, the motor expression of affect is not noted as an index of psychic economy. The qualities of the affects present in the modes of assembly of the constructions, from the child to the adult, are not analyzed. - The superposition of the diagnostic and therapeutic approach is one of the common elements; the same tools are used in different settings. - No creator mentions the quality of the environment and the major traumatic upheavals, as well as their traces, to which the population was subjected during this period of the 20th century. Jung's works are frequently quoted and taken up as a basis for reflections in these two frameworks; the influence of Jungian theories appears relatively extensive at this time. DiscussionThe memory traces left by the traumas linked to the two World Wars are little taken into account among populations who were exposed to their damage, although the games reveal traces of it. Current research on autism and old age reflects ongoing in-depth studies. A reflection comes up several times in the writings of G. von Staabs that also crosses the two fields concerned by the Scenotest, that of psychotherapy and diagnostic investigation. The reference to construction is interesting to remember, in this period of destruction of the environment; on the contrary, the game and the analysis of its free associativity in children are left in the shadows. The work of Monika Boekholt concerning the Scenotest has made it possible to present a new method of interpreting acting processes by favoring the analysis of the different modes of representation of the body in thought, from perceptual sensory traces to the work of primary and secondary identifications. During our research with children and adolescents with autism using the Scenotest, we were surprised by the attention paid by the patients to the elements to be built which, are immediately invested in building a double bottom and/or reinforcing the edges of the playing area. ConclusionThis historical study sheds light on the new fields of epistemological and therapeutic research, which could be useful in designing relevant diagnostic and therapeutic devices.