Yrjö Reenpää

Mapping the relations of measured sensation magnitudes to stimulus parameters revealed to him the structure of the phenomenal perceptual manifold and its metrics.

He outlined in an axiomatic form the psycho-physical relation fitting with Kantian epistemology and with phenomenology as presented in the first half of the century by Edmund Husserl and Martin Heidegger among others.

Applying psycho-physical methods he and his collaborators, R. M. Bergström, later his successor, Alvar Wilska, and Eeva Jalavisto among others, obtained experimental evidence of the structures of perceptual manifolds in various sensory modalities.

After his retirement he extended the philosophical considerations to include the psycho-physiological issues of mind-matter relation and discussed psycho-physiological parallelism in cases relating perceptions to evoked response data particularly in audition in the studies by Wolf Dieter Keidel and his collaborators in the University of Erlangen, where Reenpää had a visiting professorship.

Concepts arise from the noumenal contents of observations by extracting them out of their temporal frame of the act of perception, as purely timeless entities.