21. Ultimate Causes

From Advice for a Young Investigator (tr. Swanson).  The book is a revised publication of Cajal's speech upon induction into the Academia de Ciencias Exastas, Físicas y Naturales on December 5, 1897:

"Another commonplace worth repeating is that science cannot hope to solve Ultimate Causes.  In other words, science can never understand the foundation hidden below the appearance of phenomena in the universe.  As Claude Bernard has pointed out, researchers cannot transcend the determinism of phenomena; instead, their mission is limited to demonstrating the how, never the why, of observed changes.  This is a modest goal in the eyes of philosophy, yet an imposing challenge in actual practice.  Knowing the conditions under which a phenomenon occurs allows us to reproduce or eliminate it at will, therefore allowing us to control and use it for the benefit of humanity.  Foresight and action are the advantages we obtain from a deterministic view of phenomena."

It is continually fascinating to me to read about Cajal's humility.  He believes that the drilling human intellect will never penetrate some final, first layer of causes.  I think it is fair to call this unknowable knowledge "divine," in Cajal's vocabulary and association.  His satisfaction with his cosmic situation is, in my opinion, a facet of his unique genius.  I have excerpted from his explanation of his religious beliefs here, beginning at "Let us console . . ."

To understand a religious man you must understand his religion.  Cajal was not traditionally devout, but was undeniably formed in some part by Catholic education.  (I find this in his section of his Don Quixote essay where he argues that pain is the "Whip of Emotions").  He believes in something higher; something that may be material, but will never materialize.  Her name (and it is certainly feminine for a Quixote such as Cajal) could be Nature (or Truth).  She is a scientific God, in that she behaves deterministically.  To know her is to make a discovery, at which point a "veil is lifted from before (the) eyes," to quote Cajal's autobiography Recollections of My Life.  The scientist is "minister of progress, priest of the truth, and a confidant of the Creator" (Advice).

I must identify Cajal's God in order to understand his life, I said it at the beginning.  And it's coming into focus.