I have watched as much of Adam Schiff and company as I can
bear, and I certainly do not intend to watch Jay Sekulow and Pat Cipolloni, so
I shall spend some time this morning spelling out the new idea I had about Hume’s
theory of knowledge and its relation to Kant’s theory in the First Critique. The idea is of general applicability, but I
will just sketch it for the case of causal inference. This is going to be brief, and therefore
perhaps somewhat incomprehensible to those who are unfamiliar with my
interpretation of Kant.
Kant says at A106 that “A concept is always, as regards its
form, something universal which serves as a rule.” The categories are second-order rules, or
rule types. They are rules for forming
rules for the synthesis of a manifold of sensibility. More precisely, as Kant makes clear in the
First Edition so-called Subjective Deduction, they are rules for forming rules
for the reproduction in Imagination of perceptions that are elements of the
spatial manifold or diversity of sensibility.
The act of reproduction imposes on the perceptions a rule-governed – hence
in that sense a necessary, i.e., necessitated by the rule – temporal order.
Thus, the Category of Cause and Effect is a template, or
rule type, for forming specific rules for the reproduction of certain elements
of the manifold of sensibility in such a manner that some elements must,
according to the rule, be reproduced first, and then other elements must be
reproduced second. The Cause and Effect
rule type differs in this regard from the Substance and Accident rule type,
which specifies that each element can, indeed must, be reproduced first in one
order and then in the reverse order.
[The famous example of the boat and the house in the Second Analogy.]
Kant’s language breathes with the rigor and quasi-logical
tonality characteristic of his predecessors among the Continental Rationalists,
Descartes and Leibniz. It virtually commands
us to stand at attention when we are reading the Critique.
Hume, in Part III of Book I of the Treatise, begins with a brief but devastating dismantling of the
rigorous claims for causal inference advanced not only by Descartes and Leibniz
but also, more significantly, by Newton.
He then goes on to ask why it is, despite the manifest validity of this
critique, that we believe judgments of causal connection. He asks what belief is, and how it comes
about that we form and hold to such beliefs, a process that he labels “natural
belief.” His account is casual, circumstantial,
almost anecdotal, as though he were merely narrating what he has observed about
the curious doings of the [British] human mind.
It is an account best read while seated in one’s study with a fire in
the hearth and a glass of port at one’s elbow.
His answer, to put it succinctly, is that the human mind has
an inexplicable propensity, when presented in its experience with certain
patterns of perceptions [the constant conjunction of resembling instances], to
develop a disposition of a certain type.
Specifically, the experience of repeated conjunctions of resembling
perceptions triggers the propensity to form a disposition to expect an instance
of the second type when presented with an instance of the first type, and, what
is more, to confer on the idea of the anticipated instance a liveliness or
force and vivacity, which is to say, to believe that it will occur.
In short, Hume’s analysis of causal inference is that it
rests on an innate second-order disposition, a disposition to form dispositions
of a first-order nature. Thus,
structurally, Hume’s analysis of causal inference is almost identical with that
of Kant.
This much occurred to me sixty-seven years ago as a nineteen
year old Harvard senior taking his honors general examination in the Philosophy
Department. It was elaborated in my
doctoral dissertation, “The Theory of Mental Activity in Hume’s Treatise of Human Nature and Kant’s Critique of Pure Reason, and published
sixty years ago as “Hume’s Theory of Mental Activity” in the Philosophical Review. But I never asked myself why, despite advancing
such strikingly similar analyses of causal inference, Hume and Kant sound so
utterly different from one another in the Critique
and the Treatise. While re-reading Book I of the Treatise in preparation for my YouTube
lectures, the answer occurred to me. It
is hardly profound, indeed it is obvious, but I had simply never formulated it
in my mind.
Hume and Kant end with strikingly similar analyses – rules
for the formation of rules, propensities for the formation of dispositions –
but they begin at polar opposite starting points. To put it as succinctly as I can, Kant starts
with Leibniz and Hume starts with Locke.
Each carries with him on his journey the baggage of his point of origin,
each wears the clothing of his youth, sports the colors of his home team, each strives
to remain true to his intellectual upbringing even as he is breaking completely
with his past. That is why, more than
two centuries later, we still cannot help seeing them as opponents, failing to
recognize the deep similarity of their final doctrines.
Is there then no real difference between them? Indeed there is, a difference of monumental
importance. What then is it? That is a subject for another post, but the
answer can be given in five words: The
Transcendental Unity of Apperception.
