last theory we are going to look at is Phenomenalism. We looked
briefly at this in the last unit and, as you may recall, the theory
proposes that we cannot experience anything beyond the phenomena
of our perceptions. This view, similar to Idealism, states that
our knowledge of reality must be based on what we actually perceive
- on empirical evidence - otherwise, it is nonsense.
most well known form of Phenomenalism is that proposed by the English
philosopher A. J. Ayer and the movement known as Logical Positivism.
From Ayer's viewpoint, a proposition is true only if some experience
can verify it. So, the statement that the Amazon is the longest
river in the world may be measured by looking at satellite photographs
of all the world's rivers. However, the statement that "I can
turn invisible but only when I close my eyes, no one is looking
and there are no cameras, etc." is considered by Ayer to be
nonsense because there is no possible way that anyone - even the
'invisible man' himself - can verify it. This is called the Verification
Phenomenalists, all statements about the world are actually statements
about sense experience - whether actual or possible. So, although
we may not currently be able to prove that there has been life on
Mars, it may in future be possible to do so. In this sense, whereas
Idealists considered material objects not to exist, Phenomenalists
consider them 'permanent possibilities of experience'.
as a theory of truth is a form of reliabilism. What can be justified
- or verified - has meaning, what cannot be - at least potentially
- is nonsense. The methods used to verify statements are traditional
empirical and scientific ones - i.e. the senses plus scientific
equipment. As such, it is open to some of the same criticisms as
perhaps the main problem with the approach is that the verification
principle itself is too vague. How is a statement verified?
and logic are also problematic for this theory in that they are
truths that seem to be independent of sensory verification. Ayer's
answer to this was to consider them conventions of language. Similarly,
all ethical and aesthetic statements were held to be neither true
nor false because they could not be verified.
one criticism points out that the verification principle itself
is not - by its own criteria - meaningful. For, it is not an analytic
truth (a 'convention of language') and neither is there any possible
or actual sense experience that could be said to verify it.