When I first read the opening from Hobbes’ Leviathan as an undergraduate, I laughed.  I laughed heartily.   There was something clearly, and quaintly, absurd about his simple (though perhaps vaguely Rube-Goldberg-esque) chain of mechanistic causal events which for him became the workings of the universe.  From Hobbes, Leviathan, Chapter 1: Of Sense:

The cause of Sense, is the Externall Body, or Object, which
presseth the organ proper to each Sense, either immediatly,
as in the Tast and Touch; or mediately, as in Seeing, Hearing,
and Smelling: which pressure, by the mediation of Nerves, and other
strings, and membranes of the body, continued inwards to the Brain,
and Heart, causeth there a resistance, or counter-pressure,
or endeavour of the heart, to deliver it self: which endeavour
because Outward, seemeth to be some matter without.  And this Seeming,
or Fancy, is that which men call sense; and consisteth, as to the Eye,
in a Light, or Colour Figured; To the Eare, in a Sound; To the Nostrill,
in an Odour; To the Tongue and Palat, in a Savour; and to the rest
of the body, in Heat, Cold, Hardnesse, Softnesse, and such other qualities,
as we discern by Feeling.  All which qualities called Sensible,
are in the object that causeth them, but so many several motions
of the matter, by which it presseth our organs diversly.  Neither in
us that are pressed, are they anything els, but divers motions;
(for motion, produceth nothing but motion.)  But their apparence to
us is Fancy, the same waking, that dreaming.  And as pressing, rubbing,
or striking the Eye, makes us fancy a light; and pressing the Eare,
produceth a dinne; so do the bodies also we see, or hear, produce
the same by their strong, though unobserved action

The absurdity, to me, was not merely that Hobbes thought that he had figured out the mechanisms that ruled over our senses and feelings simply by expanding simple principles of interaction of bodies.  Rather, I laughed because I thought it was preposterous that Hobbes thought to account for non-physical things, like emotions and mental activity, by means of materialist mumbo-jumbo.

Curiously, I was simultaneously quite sincerely open to, if not entirely credulous of, the findings of modern psychological studies which played the exact same role–namely, making the naturalist presumption that those things which seem incorporeal (like thoughts, sensory data, and emotions) could be studied as causes of simple physical interactions observable, for instance, by means tools like nMRI.  Modern naturalist science (I’m convinced that naturalism is not in any way definitional of science, but rather a mere ubiquitous presumption of modern scientists and the in-vogue scientific paradigms) simply has a more complex version of Hobbes’ materialism.  Rather than simply positing that something “preseth on the eye”, biologists a conception of our senses as the products of a complex of chemical and physical interactions which can all be reduced, theoretically, to a naturalistic incarnation of particle physics.

Each of these two perspectives–Hobbesian materialism and modern naturalist science–has issues with the classical Cartesian mind/body dualism.  What I considered incredible in the Hobbesian perspective, I should recall, is not the given dualism ” between two sorts of ‘stuff’, material and immaterial” (as Rorty calls it), but was once an idea marked more by its novelty than its broad acceptance.  With what reasons did dualism replace materialism as the dominant metaphysical structural assumption?  Certainly a number of enticing dualist metaphysical systems exist, and we might have good reason/s–logical or practical–to accept any of these.  I am not convinced that this dualism is essentially reasonable (or for that matter, if it is, that it is reasonable that we should assume that the non-material side of this dualism should have laws similar to our empirically-derived laws for the natural world); I am likewise not convinced that the material dualism has any cogent appeal over metaphysical tri-ism, quad-ism, or infinit-isms (do metaphysicians have terms for these?), other than theoretical parsimony.

Rorty speaketh

Richard Rorty opens Philosophy and the Mirror of Nature, Chapter 1 with this to say about dualism:

Discussions in the philosophy of mind usually start off by assuming that everybody has always known how to divide the world into the mental and the physical–that this distinction is common-sensical and intuitive, even if that between two sorts of “stuff”, material and immaterial, is  philosophical and baffling”

While I don’t think that this position is completely fair or accurate, Rorty’s point is well-made.  If we need a dozen or more metaphysical systems for bridging that “between” in the mind/body dualism–epiphenominalism, parallelism, occasionalism, and their ilk–and the whole dualist project is so difficult for us to fine-tune, what makes this dualism seem so obvious?  I suspect Rorty is not just being eristic when he implies that its our dogmatic entrenchment which makes this dualism seem natural, not some objectively-apparent metaphysical substructure.  This dogmatic entrenchment, I think, is what made Hobbes’ materialist metaphysics seem so quaint and rediculous; meanwhile, my dogmatic entrenchment in the authority of modern scientific findings allowed me to provisionally accept a sort of materialist perspective.  Perhaps it is unfair of me to so readily accept one while simultaneously poo-poo-ing the other.

I enjoy Rorty’s criticism of this dualism, but I think my position is still largely gauche to his.  We should not ignore the predominant metaphysical assumption of dualism–nor, conversely, the metaphysical (or physical) presumption of monism/materialism (or other metaphysical -isms).  We simply ought to be aware of, but not necessarily strictly opposed to, our dogmatic assumptions.  Likewise, we should take note when our various presumptions do not jibe well.  Do we assume dualism, yet affirm the findings of research that presumes or requires monism?  If so, is it merely the result of the brute cultural force of one over the other, or are there good reasons for believing both?  Certainly we might simply mean “monism” and “dualism” in different ways.  Dualisms, of course, may be distinctions between “subtances”, “properties”, or “predicates”, among other things; or perhaps it is fair of us to utilize dualist assumptions in a monist reality or monist assumptions in a dualist reality, if they get us the practical results we desire in some parsimonious way in some areas.  In the same way that we still utilize Newton’s laws for some gravity calculations, despite the existence of more precise post-Einstein calculations, it may simply be the best to use one or the other as a tool.  By this point you surely have figured out that this is my pragmatic proposition for an approach to metaphysics; It is my belief that a “dualism assumption awareness” campaign is much more likely to give us the results we desire than a “dualist-smashing” campaign which it seems to me Rorty is using to get us to agree to presume materialism for pragmatic purposes (corrections/comments greatly appreciated!).