Peter Hobson’s The Cradle of Thought is a philosophically and scientifically informed discussion of how thought develops in early life. Hobson’s main argument is that “interpersonal engagement contributes to the development of the mind – and [that] disordered interpersonal relations affect development of thinking” (p.143). He discusses many scientific studies which show how the level and nature of interpersonal relationships can impact the capacity for thought, suggesting deficient interpersonal relationships can lead to impoverished thinking.
Hobson highlights this through discussing individuals who are often not as capable of interpersonal interactions as most humans. He primarily discusses autism in detail, suggesting the usual thinking of autistic individuals (such as theory of mind differences) arise from lack of normal social and emotional interactions in early life. He heavily emphasizes that autism has a genetic component which results in biological differences (rejecting notions of poor mothering causing autism which some psychoanalysis used to believe) but argues the abnormal thinking itself is not primarily just due to biological difference. Rather, the biological differences result in difficultly interacting normally socially and emotionally, and this abnormal social and emotional experience results in abnormal thinking.
One might ask, why not just say the biological differences are responsible for both the abnormal interactions and for the abnormal thinking? Hobson uses a novel strategy to answer this question, primarily by looking at other types of individuals who also can face difficulties interacting normally. He considers individuals who are blind from birth and individuals who had very little social or emotional interaction in early life when raised in Romanian orphanges. These individuals often could not relate to other people in early life in the same way as most children. He then shows that these individuals sometimes develop some symptoms of autism, at substantially higher probabilities than would occur at random. Autistic individuals have biologically abnormal minds, blind individuals lack sight and Romanian orphans presumably have no major biological differences, yet all can exhibit some similar behaviour we associate with autism. Therefore, Hobson argues, some autistic behaviour is not directly the product of the biologically abnormal mind, but the biologically abnormal mind sets up abnormal interpersonal relationships and those interpersonal relationships result in symptoms associated with autism. Hobson also provides some evidence from how mothers with boarderline personality disorder interact with their children and how chimpanzees lack some parts of human socialising, suggesting both these cases can contribute to less than fully developed thinking.
Even though considered a developmental disorder, there is often a suggestion within scientific literature that the psychological development purely follow biological developments, rather than biological development resulting in psychological developments which then result in further psychological developments. I think a simple biological leading to psychological approach often present in modern science is far too simplistic, but I am unsure whether I think Hobson is correct or if I prefer a middle ground between Hobson and that modern science picture. Reguardless, the book is highly recommended for raising some important questions, presenting a solid evidence basis (often from very diverse sources which are not usually discussed in the context of autism) and for being highly accessible, being effectively popular philosophy and popular science.