Chapter 11 Causal Circuit Explanations of Behavior : Are Necessity and Suf fi ciency Necessary and Suf fi cient ?

In the current advent of technological innovation allowing for precise neural manipulations and copious data collection, it is hardly questioned that the explanation of behavioral processes is to be chiefly found in neural circuits. Such belief, rooted in the exhausted dualism of cause and effect, is enacted by a methodology that promotes “necessity and sufficiency” claims as the goal-standard in neuroscience, thus instructing young students on what shall reckon as explanation. Here I wish to deconstruct and explicate the difference between what is done, what is said, and what is meant by such causal circuit explanations of behavior. Well-known to most philosophers, yet ignored or at least hardly ever made explicit by neuroscientists, the original grand claim of “understanding the brain” is imperceptibly substituted by the methodologically sophisticated task of empirically establishing counterfactual dependencies. But for the twenty-first century neuroscientist, after so much pride, this is really an excess of humility. I argue that to upgrade intervention to explanation is prone to logical fallacies, interpretational leaps and carries a weak explanatory force, thus settling and maintaining low standards for intelligibility in neuroscience. To claim that behavior is explained by a “necessary and sufficient” neural circuit is, at best, misleading. In that, my critique (rather than criticism) is indeed mainly negative. Positively, I briefly suggest some A. Gomez-Marin (&) Behavior of Organisms Laboratory, Instituto de Neurociencias CSIC-UMH, Alicante, Spain e-mail: a.gomezmarin@umh.es © Springer International Publishing AG 2017 A. Çelik and M.F. Wernet (eds.), Decoding Neural Circuit Structure and Function, DOI 10.1007/978-3-319-57363-2_11 283 available alternatives for conceptual progress, such as adopting circular causality (rather than lineal causality in the flavor of top-down reductionism), searching for principles of behavior (rather than taking an arbitrary definition of behavior and rushing to dissect its “underlying” neural mechanisms), and embracing process philosophy (rather than substance-mechanistic ontologies). Overall, if the goal of neuroscience is to understand the relation between brain and behavior then, in addition to excruciating neural studies (one pillar), we will need a strong theory of behavior (the other pillar) and a solid foundation to establish their relation (the bridge). 11.1 Explaining Explanation (Prelude) A cat is chasing a mouse all over the house. When we observe this, or any other phenomenon, we can be in the presence of it for its own sake—we can know it in its immediacy. If we are curious; however, we are soon compelled to ask what is going on. Our quest for understanding begins. The rational mind seeks an explanation. But, what does it mean to explain a phenomenon? The canonical approach says that to explain is to find the cause. It is known since Aristotle that the notion of causality has a quadruple structure: understanding why something is what it is requires to identify its material cause (what it is made of, namely, the tangible substrate from which something can take place; i.e., nerve cells, muscle, bone), formal cause (what it is to be, namely, what something can become without contradicting itself; i.e., being a mouse and a cat, a predator and a prey), efficient cause (what produces it, namely, the source of change; i.e., hunger, scent, sight), and final cause (what it is for, namely, that for which it becomes and perfects itself; i.e., the need to escape the mouse, sustain life, the good). Science, in its reaction against the teleology of the nineteenth century, eschewed the final cause. Since the formal cause appears uninteresting or incomprehensible, and the material cause is taken for granted, this left the twentieth-century scientist with the main pre-occupation of dissecting efficient causes. In the case of the cat, to find out what brought about chasing behavior. More generally, to explain is to substitute fact by abstraction. The notion of causality is a vast topic, and this is not the place to try to give a complete account. It is of interest to briefly note that it has been claimed that «in advanced sciences (.) the word ‘cause’ never occurs» (Russell 1913). Indeed, modern physics has succeeded by finding laws (quantitative invariant relations of variables) rather than causes (chains of antecedent–consequent events). «Teleology has been discredited chiefly because it was defined to imply a cause subsequent in time to a given effect. When this aspect of teleology was dismissed, however, the associated recognition of the importance of purpose was also unfortunately discarded. Since we consider purposefulness a concept necessary for the understanding of certain modes of behavior we suggest that a teleological study is useful if it avoids problems of causality and concerns itself merely with an investigation of purpose. » (Rosenblueth et al. 1943). 284 A. Gomez-Marin