Some Observations on Paleologic Thinking in Borderline Personality Disorder

Paleologic thinking, a prelogical mode of reasoning described by Silvano Arieti, is characterized by emotion-driven, retrospective reasoning and has been observed in severe mental illnesses such as schizophrenia. The author explores its relevance to borderline personality disorder, an area that has been historically understudied. Patients with borderline personality disorder often regress into paleologic modes of thought during interpersonal distress, resulting in illogical conclusions driven by feelings rather than evidence. It is argued that this process underlies symptoms of paranoia, misperceptions of rejection, and interpersonal dysfunction. Historical perspectives linking borderline personality disorder and schizophrenia, as well as empirical findings from unstructured psychological tests, highlight overlaps in thought disorders between the two conditions. Clinical implications suggest that addressing paleologic thinking can improve treatment outcomes. Structured psychotherapies, such as transference-focused psychotherapy and dialectical behavior therapy, offer pathways to target and mitigate the impact of this pathological reasoning process in patients with borderline personality disorder.