Understanding Matte-Blanco

DEAR SIR,

In a very thorough reply to my paper 'Understanding Matte-Blanco' (this journal 1984,

65) which is found in the same volume, Matte-Blanco seems not to have understood my single, though I believe crucial, criticism of Bi-logic, namely that it is inconsistent. He is under the impression that because the two basic principles (Generalisation and Symmetry) do not always contradict, or only contradict in some specific aspect, his system remains intact. I would like to correct this impression.

Matte-Blanco teaches us that the Unconscious does in some measure use two valued logic and that the principle of Generalisation (Predicate thinking) represents this. But the 'deeper' the Unconscious manifestation the less respect for the two valued logic and Freud has listed at least four ways the Unconscious proper violates the straight and narrow path of conventional logical thinking. These violations are largely explained by his Principle of Symmetry (relations are reversible). Bi-logic, the logic of the Unconscious is the intertwining of these two principles.

I have no quarrel with this imaginative perspective on the Primary and Secondary processes of the mind and when Matte-Blanco proposes to allow that at some times these principles contradict and at other times they do not, we can agree that in his perspective this is how things are in the Unconscious. However, from a strictly logical point of view, for a logic to be a valid logic (i.e. never to lead us from true statements to false ones) we require that its basic principles should never contradict. This is where he makes a serious error of logic when he says:

It is no wonder, then, that the principle of Symmetry, which describes the violations of bivalent logic, should at times—not always be in contradiction with the principle of Generalisation—a truism (p. 457)

and again:

In other words when the principle of Symmetry holds, the principle of contradiction is not always violated (p. 457)

and again: