c CUNYB/Clarke December, :
Descartes and Princess Elizabeth the most productive intellectual conversations in Descartes’ mature years,
which eventually amounted to fifty-nine letters. Even when Elizabeth left
the United Provinces in, her departure did not interrupt her cor-
respondence with her philosophical tutor. Many years later (in) she
was appointed abbess of Herford, to which she welcomed Anna Maria van
Schurman together with her suspiciously close spiritual advisor, Jean de
Labadie, in.
Elizabeth’s first letter to Descartes (May) mentioned that she had
asked Regius a philosophical question when he had visited The Hague ear-
lier, and that Regius had referred her to Descartes for an expert opinion.
The question was central to the Utrecht dispute, so that Elizabeth’s read-
ing of theMeditationsmerely helped to underline the intractability of that
controversy. Descartes had argued in his physics that any communication
of motion from one body to another occurs because of a collision between
the two bodies. Yet it seems that, when we decide to perform some action –
where the decision is understood as a mental act – the mental act affects
the flow of a subtle fluid in our nerves (called animal spirits) and that this,
in turn, moves our muscles. This was a case, therefore, of a mental act
causing the motion of a physical body. Elizabeth had identified a funda-
mental anomaly in the interaction between mind and body, and she asked
her question as follows:How can the human soul, which is only a thinking substance, determine the movements
of the animal spirits in order to perform a voluntary action? It seems as if every
determination of movement results from the following three factors: the pushing of
the thing that is moved, the manner in which it is pushed by the body that moves it, and
the quality and shape of the latter’s surface. The first two presuppose that the bodies
touch, while the third presupposes extension. You exclude extension completely from
your concept of the soul and, it seems to me, it is incompatible with being an immaterial
thing. That is why I am asking for a definition of the soul that is more specific than
what is provided in yourMetaphysics.... (iii.)Descartes’ immediate reply (May) was wrapped in diplomatic
formalities, acknowledging the honour of receiving commands from his
royal correspondent and offering to travel to The Hague, at her conve-
nience, to explain himself orally. Apart from the obsequious compliments,
Descartes also provided the first genuine effort on his part to philosophize
about how the human mind and body interact.
Descartes suggested that, when we think about any reality, such as the
human mind or material bodies, there are a few fundamental concepts in