Yves asked:

Metaphysics can be defined as the science that tries to get to the truth behind things as they appear
(Cf. F.H. Bradley's Appearance and Reality). But whatever lies behind appearances must be known
by inferences from those appearances. Now in any deduction, it seems there must be both a
universal proposition and a particular proposition. The particular proposition would be one taken from
the appearances of things.

What would the universal proposition be? And why? It looks like metaphysics is a very problematic
science posing as something very certain. In fact, there's hardly anything philosophers differ so much
on than metaphysics.

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The proposition, 'whatever lies behind appearances must be known by inferences from those
appearances' is a fair characterization of scientific knowledge. Typically, the scientist puts forward a
hypothesis, in the form of a universal proposition from which statements about 'appearances' — i.e.
predicted experimental results — can be derived. If the actual results conflict with the prediction, then
the hypothesis is rejected.

The problem with metaphysics is that conflicting metaphysical theories agree in all the experimental
predictions that can be derived from them. Whether you are a Berkeleian idealist or a realist, two
masses attract one another with a force inversely proportion to the square of their distance.

Here are two strategies that one could adopt in response to this challenge: The first is to seek a
purely logical derivation of universal metaphysical propositions that does not require any additional
premise concerning empirical appearances. The Presocratic philosopher Parmenides is the first
recorded example of an attempt to follow that method, in arguing for his theory of 'the One'. In the
20th century, The metaphysician John McTaggart used this approach in his treatise The Nature of
Existence.

The second strategy is to seek to uncover an incoherence or 'contradiction' inherent in the world of
appearances, or the way in which we think about appearances. The Presocratic Philosopher Zeno
sought to undermine belief in change and plurality by showing how our beliefs about the world of
appearances lead to insoluble paradoxes. In his treatise Appearance and RealityF.H. Bradley argued
that appearances are inherently 'self-contradictory', and that therefore there must exist an 'Absolute',
where these contradictions are resolved.

These alternatives do not exhaust all the options. A third possibility would be to view 'metaphysics' as
involving an investigation into the conceptual framework which we apply to our familiar world, either
with a view to its improvement, or to lay bare aspects that had previously been hidden. In very
contrasting ways, Whitehead in Process and Realityand Heidegger in Being and Timeboth adopt
this general approach. The Oxford philosopher P.F. Strawson in his book Individuals(1959)
contrasted his own 'descriptive' exploration of our conceptual framework with the 'revisionary' views of
metaphysicians such as Berkeley or Whitehead.

I think that all metaphysics can ultimately be is a way of directing our attention to aspects of our world
that we had not noticed before. For example, the nature of the subjective viewpoint, or our experience
of the passage of time. I am sceptical about the possibility of there being such a thing as a
metaphysical 'theory'. Simply to describewhat we see when we look at the world in this way is still a
tremendously difficult task.

Geoffrey Klempner