Knowledge is
power, established by arguments which are made up of statements that can be
true or false, and are in turn made up of subjects and predicates. Consider
this classic argument:
(S1) All persons are mortal
(S2) Socrates is a person
(S3) Therefore,
Socrates is mortal
The argument is
clearly made up of three statements, that may each be true or false, and
together say something consequential about Socrates. This knowledge about the
mortality of Socrates, established by argument, is clearly a kind of power.
S1 is complicated
so let’s start with S2: ‘Socrates’ is the subject and ‘person’ is the
predicate. Traditionally, the subject is the substance and the predicate is the property. So S2 says that there exists a substance
‘Socrates’ that has the property of being a ‘person’. Similarly, S3 says that
this same substance also has the property of being ‘mortal’.
Back to S1, it is
the crux of the argument by identifying ‘person’ with ‘mortal’. If the
statement was ‘A person is mortal’, it would not say much. S1 says that all persons are mortal. The subject is not
‘all persons’ but the class of all persons through all time. This means that
person1 is mortal, and person2 is mortal, and person3 is mortal, etc.
There is
something off here. I suspect most of us believe S1 but how can we justify this
belief? That is the problem of induction. I will role play that you are a
skeptic about the mortality of all persons and do my best to convince you of
the truth of S1.
There are three
groups of persons: (x) those that have died, (y) those currently alive and (z)
those yet to come into this world. Obviously, as time marches on persons are
born and die, moving from group z to groups y and then x.
I will start with two tests: a person is born of a person (with some arbitrary first person); and a person is mortal if (s)he died. We can test the tests with an x-case we can agree on. Take Whitney Houston. She was born of a person and (sadly, recently) died, so she is mortal. Therefore, the statement ‘Whitney Houston is mortal’ is true. At a point in time, we can enumerate each person in group (x) that has ever died and apply this argument to prove their mortality.
I will start with two tests: a person is born of a person (with some arbitrary first person); and a person is mortal if (s)he died. We can test the tests with an x-case we can agree on. Take Whitney Houston. She was born of a person and (sadly, recently) died, so she is mortal. Therefore, the statement ‘Whitney Houston is mortal’ is true. At a point in time, we can enumerate each person in group (x) that has ever died and apply this argument to prove their mortality.
What about
y-persons, those like you and me currently alive? Unless I happen to outlive such persons, I
cannot (by this argument) establish that they are mortal. Of course, I cannot outlive myself so you may have to confirm my mortality. The situation is worse for z-persons yet to be born. But that
doesn’t make sense. We know that all persons are mortal so why is it so hard to prove?
This is where
philosophy gets fun. Perhaps we are wrong about what we think we know. Maybe you and I are not mortal. Was Irene Cara right when she sang, "I'm gonna live forever"? Or maybe my tests are missing the point. The very
requirement of a mortality test betrays a lack of understanding about
personhood. If you agree, then we don’t need exhaustive surveys and depressing body
counts to establish mortality. On this view, mortality is just part of what it
means to be a person, in the same way that being born of a person is also part
of what it means to be a person.
We now have two
alternatives: either ‘all persons are mortal’ is (A1) a statement independent
of experience (if you know it is a person, then you also know that it is
mortal) or it is a statement (A2) about our experience with people, that they
eventually die. We already saw that if S1 is an A2, we run into the induction
problem. So S1 is an A1 statement, that is, it is true independently of experience.
What would make
S1 as A1 true? Generally speaking, statements can be true either (B1) by
definition or necessity, where the predicate is ‘contained’ in the subject, or
(B2) for some contingent reason. It is clear that any B1-type statement is also
a A1-type statement. For example, ‘A person is born of a person’ is clearly
independent of experience (A1) since it is true by definition (B1).
If you accept
that ‘all persons are mortal’ is prior to experience (an A1 statement), you may
still not accept that this is a matter of definition (not B1). Notwithstanding
creation, I cannot imagine a natural person that is not born of a person ('natural' here is to exclude artificial persons like corporations). However, I can imagine a natural person that does not ever die, as Irene Cara does . So, if S1 is an A1 statement but not also a B1
statement, what is it?
More generally: are there
things that can be known independently of experience which are not a matter of definition? This was Kant’s pregnant question. He called:
A1 – a priori statements
A2 – a
posteriori statements
B1 – analytic
statements
B2 – synthetic
statements
If I am right that 'All persons are mortal' is a A1-B2 statement or a synthetic a priori statement, then Irene Cara and the rest of us are mortal. This is the depressing part. However, the Kantian
question is an entry point into the reframing of philosophy into the modern outlook.