Parsing Categories of Belief
Why Early Modern M&E divides
belief into two types:
Sensory & Mathematical
Ways to Categorize Beliefs
• According to subject matter (e.g., theological,
scientific, aesthetic, political, practical,
philosophical, anthropological, etc.)
• According to evaluative criteria (e.g., stupid,
crazy, misguided, well-founded, hard-headed,
logical, rational, self-evident, etc.)
• According to the means by which the beliefs
are formed (e.g., a posteriori/sensory beliefs,
a priori/mathematico-logical beliefs)
Why the Early Moderns Chose Door #3
Early modern thinkers had the following insight: given
that all our beliefs about ourselves, our minds, and the
world around us, are built upon a foundation if ideas (i.e.,
their content is produced by an act of judgment that
combines ideas into the form of judgments/propositions/
assertions), if we knew how we come to have all the
different kinds of ideas we in fact do have, then we would
then be able to answer the primary question in
epistemology: “how are justified true beliefs
possible/actual?” AND, answering that question would
allow us to answer the main question of metaphysics:
“What exists, and what is the nature of its existence [i.e.,
how is the determinable determined?]?
Thus, Descartes, Locke, Leibniz, Hume, Berkeley,
Kant, Malebranche, Wolff, Reid, Rousseau, et al.,
thought that first philosophy = the pursuit of a
true theory of mind/mental content.
It is for this reason that my question (“What are
the two kinds of beliefs that are required in
order to pursue the scientific study of nature?”)
is answered by Early Modern Philosophers this
way: 1) sensory beliefs, and 2) mathematical
beliefs.
And why is access to the formation of true
instances of these two kinds of beliefs a
necessary condition of doing the kind of natural
science being pursued by Newton, Galileo,
Brahe, LaPlace, et al.? Because that kind of
science, and any kind of science based on the
scientific method, depends on 1) formulating
hypotheses [often using mathematical
descriptions to express them], which are tested
using 2) observations [entirely available to
human minds by means of sense perception] to
explain natural phenomena associated with
those observations.
The Primary Early Modern
Philosophical Project
To discover a model of mind that offers the correct
etiology of all ideas used to formulate true beliefs about
1) sensory experience, and 2) mathematical propositions
and reasoning. It was believed that this model of mind
would provide a foundation for the primary assumptions
on which any science of nature that tests theory on the
basis of observation is grounded. This model will establish
how, where, when and why some of our ideas accurately
represent the world outside our minds, and how we can
be sure that our beliefs based on these ideas also reflect
the objective state of affairs in that world.
Three Approaches to this Project
• Rationalism (heyday: 1640-1700)
Proponents: Descartes, Spinoza, Leibniz, Arnauld,
Malebranche, and Wolff.
• Empiricism (heyday: 1690-1780)
Proponents: Locke, Berkeley, Hume, Hobbes, and Reid.
• Transcendental Idealism (heyday: 1780-1800)
Proponents: Kant (and also, Fichte)
What Distinguuishes Each Approach
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•
•
Rationalism—patterns philosophical knowledge after mathematical beliefs: the
same rigorous order of reasons and consequences, the same certainty and
independence of all contingency, that could be found in Euclid, these thinkers
sought to bring to philosophy. Basic principle: innate ideas available to the mind by
means of pure reason are more likely to reflect the character of the world as it is,
and hence reason is the proper faculty of knowledge.
Empiricism—patterns philosophical knowledge after empirical beliefs. Basic
principle: only beliefs using ideas drawn from sense perception can be trusted to
represent the world accurately, since sense perception is our only means of access
to the world we hope to comprehend and explain, and hence, sense perception is
the proper faculty of knowledge.
Transcendental Idealism—both traditions make a common mistake (assuming that
there is only one faculty of knowledge) while promoting one truth missing from its
competitor (both reason and sense perception are necessary if knowledge of the
objects of experience is to be possible), and hence, experience, and so knowledge
of nature, depends on: sense perception + structures of the mind.