Neuroscience, the microscope and the truth: personal philosophical considerations by a professor emeritus of neuropathology and neurology.

The article starts from the conception that the world is introduced in our mind though linguistic categories and that between us and the world there is always the language. This implies that to denominate still means to know. The visual pathway is described from the retina to the occipital cortex with the related phenomena of the recognition of the external world, through the Gestalt psychology, the reciprocal influence of sign/receptor, the mental images or patterns, the cognition, the conscience and memory. As an example, the microscope is presented as a tool for exploring the external world. The scientific objectivity is given by the dialectic with the scientific inter-subjectivity that, if abandoned, may give origin to mistakes or dangerous ideologies. The scientific truth is not absolute and perennial, but contingent and temporary and it is validated by the epochal parameters. The features outlined may apply to scientific research, clinical reasoning and also to the general behavior.