To the psychologists, it is partly just a matter of science. A recent issue of The Psychologist carried an article on this very subject. Professors Anne and Alan Clarke argued that children who suffer severe early adversity but whose subsequent care is good "progress on average to normality". Current circumstances are held to be the key to adjustment, and the Clarkes conclude that "early experience by itself does not predestine the future".
They gloss over the hundreds of studies that show that the kind of care a child receives between the ages of six months to three years largely determines its pattern of attachment in later life.
However, it is impossible to wholly refute the Clarkes' thesis until a large sample of children has been followed from before birth until old age in sufficient detail. Such a study would measure the care they receive by direct observation of unprecedented frequency and make regular checks on their subsequent influences. It would also be designed in such a way as to be able to detect genetic influences.
But science is not the only reason for hostility to the role of early experience. Most psychologists associate it with Freud, and he is a dirty word in a profession largely dominated by behaviourist and cognitive theories that ignore the inner world of fantasy, emotion and motivation.
As all too many undergraduates have discovered, most academic psychology courses devote at best only a couple of lectures to psychoanalysis. Being taught a psychology that ignores subjective experience is like doing a cooking course in which the preparation of food for consumption is rarely even mentioned, let alone practised.
The trouble with experience is that it is difficult to measure, and if you cannot measure something you cannot write a paper about it. Publications are the only means for advancement in psychology. Thankfully, in recent years there have been signs that psychologists are beginning to address the problem of how to measure inner life. They were, anyway, incorrect in their assumptions about Freud. Read Freud closely and it is clear he attaches little significance to the direct impact of parents in early life. What children make of how they were cared for is given far greater prominence.
Freud devised the theory that sexual abuse causes neurosis, only to recant soon afterwards. In its place he put the Oedipus complex, the idea that it is the child's desire for parents which is the problem, not the other way around. Despite this reversal, psychoanalysis has wrongly been equated with "blaming the parents" in most people's minds.
But surveys of psychologists usually place Freud top of the list of the "most influential psychologists of all time". This suggests a certain ambivalence, as analysts would put it - they both esteem and rubbish Freud.
There may be some truth in the claim of analyst Alice Miller that the real reason for the hostility to early experience is that all of us are terribly reluctant to acknowledge the damage done to us by our own parents, including psychologists. When we are tiny we rely totally on parents and, however badly they behave, we dare not criticise them for fear, ultimately, of death. This habit of protecting parents endures into adulthood. Added to this is the painfulness of recalling the many distressing experiences that all of us suffer to some degree. Perhaps we would rather not think about injuries done to children because of the pain of recalling those done to us.
This argument extends far beyond academic psychology. Our peculiarly British hostility to early experience is visible in our preference for animals over children. Because we value childcare so little, we may have more disturbing childhoods, creating more for us to repress and adults who are more hostile to childhood. Both children and psychoanalysis receive a warmer reception on the Continent.
The hostility of psychiatry to early experience is easier to explain. Psychiatrists are taught a mechanistic view of mental illness: it is an abnormality of the electro-chemistry of the mind which is best fixed by physical methods (pills or electric shocks). The notion that mental illness could be caused by early trauma is seen as a challenge to this view - although this is a misapprehension. The fact that a brain's electro- chemistry is abnormal tells us nothing at all about the cause of the abnormality.
There is a growing body of evidence that repeated exposure to abuse as a child sets abnormal levels of certain brain chemicals that endure into adulthood. In the same way, low status and economic inequality are associated with all manner of measurable changes in brain chemicals. The way the evidence is unfolding, our characteristic patterns of brain chemistry appear to reflect our past and present environments far more than our genes.
But it is asking a lot of psychiatrists to concern themselves with early experiences, in much the same way that prison officers cannot easily be expected to take their prisoners' childhoods into account when trying to control them.
The job of psychiatry is extremely stressful. Their patients are often infuriating, obtuse, depressing and difficult to treat. Given the heavy caseloads and grossly inadequate training of psychiatrists, it is understandable if some prefer to view their charges as inexplicably having a screw loose.
Oliver James's book, `Britain on the Couch - Why We're Unhappier Compared With 1950 Despite Being Richer', is now available in paperback (Arrow, pounds 7.99)