The development of logical-mathematical thought is a natural inborn characteristic of the human mind; and yet the same mental apparatus responsible for the "logical correctness" of thought is at the same time the generator of other thought processes that seem to be alien to the commonly shared logic that is the basis of our everyday communication. These are the processes that we find principally in neurotic or psychotic symptomatology and in dreams, and that appear to us as "absurd" or - to use the synonym - "illogical".

If we agree with Money Kyrle that the patient, whether clinically ill or not, suffers from "misunderstandings and unconscious delusions", the problem of the meaning, or the logical meaning, attributed to experiences becomes a relevant part of the misunderstanding linked to the psychic disturbance - a matter that traditionally is dealt with by psychoanalysis. These misunderstandings are linked to emotive-affective problems that become translated into cognitive problems in which certain logical aspects can be focalized.

Works about logical-mathematical thought appear fairly frequently in psychoanalytic literature, both regarding the use of models as well as at a more theoretical level, and this latter fact encourages us - along with Skelton - to suggest that it may be possible to trace a tradition of logic in Psychoanalysis, in which S. Freud, S. Ferenczi, I. Hermann. Domarus, I. Matte Blanco, J. Lacan and W. Bion would coincide.

In the works of authors who have dealt with these matters, the contaminations between psychoanalysis and the logical-mathematical disciplines vary considerably. Some psychoanalysts who have written about the origins of thought, suggesting a kind of identification between thought and logical thought, and including in the latter the origins of mathematical thought, have investigated the origins of the development of logic and of mathematics considered as a normal human capacity. Among these we find Ferenczi and Hermann who, amongst other things, has also written about illogical thought procedures linked to certain neurotic pathologies. Others such as W. Bion have not only made use of a broad mathematical type of model, but have also tried to "logicize" psychoanalysis especially concerning the communication of the "psychoanalytic event" constituted by the session (the grid). Others such as Matte Blanco have elaborated a model of the mind entirely of the logical-mathematical type that presumes to provide new points of view not only to psychoanalysis but also to the science of Logic. Nor is there any lack of specific contributions (R. Fine, V. Rosen) on the development of abstract thought and of mathematical talent or, vice versa (J. Canestri, S. Oliva), on the difficulties of developing and using this type of mental functioning.

Inasmuch as the development of logical-mathematical thought includes functions that play a fundamental role in cognitive development and in reality relations, this type of research continues to represent a field of study that has been widely covered by various non-psychoanalytical schools of thought. Some of them, even though on the basis of very different theoretical presuppositions and models, have arrived at observations and conceptualizations that present certain affinities with those elaborated in the psychoanalytic field.

Among these there is the research carried out by the cognitavistic school, associating to the emotive valence of the information the eventual disturbance in the elaboration of the same; a disturbance that can become a cognitive deficit. Similarly, we may mention the genetic epistemology of J. Piaget who sees the realization of the mental apparatus, and specifically its functions connected with logical-mathematical thought, as a construction and actualization of genetically determined structures, operated by the subject in relation to the environment.

This short presentation is to illustrate our intention that this space should be open to contributions from a variety of disciplines, and to invite the participation of anyone who shares these interests.