Stephen E Braude. The Limits of Influence: Psychokinesis and the Philosophy of Science. New York and London, Routledge and Kegan Paul, 1986.
Should the evidence for psychokinesis be accepted? Do psi phenomena conflict with the theories of modern physics? Is it possible to devise a coherent theory of PK? Stephen Braude's answers to these questions would be yes, no and yes. He begins by arguing that the nature of PK makes it impossible to reveal any important facts about it by conducting laboratory experiments. As we do not know what PK is and have no coherent theory as to how it operates, we cannot devise experiments which would clearly indicate whether or not such phenomena are real or illusory. Braude thus favours a re-examination of the non-experimental evidence, which these days receives little serious consideration from the parapsychologists.
He devotes a great deal of space to accounts of phenomena produced by physical mediums, concentrating on D. D. Home (1833-86) and Eusapia Palladino (1854-1918). An account is ,also given of the famous levitating priest, St Joseph of Copertino (1603-63), In the case of St Josepb, it is disappointing that he cites only secondary sources for the descriptions of the alleged levitations.
As Braude is a philosopher his main concern is to try to devise a theory to describe PK. He is well aware of the difficulties involved, as he admits that "... there remain serious doubts as to what broad ranges of phenomena PK theory must cover." and "... it is far from clear how 'psychokinesis' should be defined, even provisionally". However, he proposes to define PK as "the causal influence of an organism on a region r of the physical world, without any known sort of physical interaction between the organism's body and r", Now this raises the obvious problem that if we know of no physical connection between the organism and r then we have no reason to make any connection between what the organism does and what happens in the region r.
This objection can be dealt with by referring to the evidence for physical mediumship, for example the phenomena associated with D. D. Home. Braude apparently assumes that Home caused the phenomena, but without using any known physical methods (such as those that would be used by conjurers) .
Braude's interest in physical mediumship arises from his objection to the idea of PK as a microscopic phenomenon operating at the quantum level, and thus producing the kind of results revealed only by statistical analysis , such as highly improbable departures from randomness in long series of card-guessing experiments. He favours the idea that PK may operate on a large scale and considers that it may account for various anomalous events or circumstances. "For example, it could explain why some soldiers escape serious injury, despite taking repeated heroic risks on the battlefield." However, it does not need PSI to explain this; the laws of statistics can easily account for such observations.
Although Braude provides some material for metaphysical speculation, including a chapter on the concept of retrocausation (which would require much more space than I have available to do it justice), he does not succeed in formulating a scientific theory which could be used to test apparent PK phenomena. However, this book is an interesting addition to the literature on the subject, but is perhaps of more interest to philosophers than to parapsychologists. - John Harney, from Magonia 24, November 1986.