Evan Mowry
Intro. to Philosophy-Written Assignment
9/14

Accompanying Questions:

a: deductive
b: inductive
c: deductive

d: valid, and sound
if p, then q
p is true
q must be true

e: valid, and sound
if p, then q
p is true
q must be true

f: invalid, and sound
if p, then q
q is true
p must be true

g: valid, and sound
if p, then q
not q
then, not p.

h: valid, and sound
if p, then q
not q
then, not p

i: invalid, and sound
if p, then q
not p
then, not q

Hypothetical Syllogisms

If I am 18, I am an adult. (true)
If I am an adult, I can drink alchohol. (false)
If I am 18, I can drink alchohol. (false: invalid and unsound)

If you can swim above water, you can breathe.(true)
If you breathe, you will not drown.(true)
If you can swim above water, you will not drown. (false: invalid and sound)

Further questions to accompany the writing assignment

1a) If a person likes philosophy, then they must be a philosopher.
1b) Philosophers understand philosophy. Marty does not understand philosophy. Therefore, Marty is not a philosopher. The argument is that just because a person finds enjoyment in something, does not mean they understand what is going on.
1c) Yes, obviously. It is a valid, sound argument that refutes the previous definition of a philosopher (as Marty cannot be both a philosopher and not a philosopher at the same time).

2a) Yes, the argument is valid. It is a hypothetical syllogism, and is (hyopthetically) true. I am unsure of the make of our textbooks, and whether all Lemke's 1201 classes use the same textbook.

3a) If I am not wholly spiritual, then I am wholly physical. (P iff Q)
3b) The argument is not sound. The created conditional (3a) is untrue. One may be physical and spiritual at the same time. To make it a sound argument, "wholly" must be edited out of the antecedents, creating this argument.

If I am spiritual, I exist.
If I am physical, I exist.
I am either physical or spiritual, or both.
Therefore, I exist.

4a) "All fields of thought" is, like most absolutes in philosophy, extremely subjective and impossible to utilize. Either only those fields of thought that a person has access to are considered (making this a valid and sound, although poorly written, definition), or all fields of thought are infinite and cannot be comprehended by a single human. According to this definition, the only true philosophers are computers and God.
To correct this, I would propose a more specific definition.

x is a philosopher iff x attempts to understand philosophy

To be cute, we could add "habitually" to the latter part. This is more broad, but it really is more precise than the other, also. Of course, you still have to define philosophy, but that wasn't in the assignment, and I might not even do it if it was.

"If we should theorize that the whole of space were limited..."

In his questioning of the then thought to be finite nature of the universe, Lucretius raises the question of what reasonable thing could happen to an item reaching the limit of space. The argument brought forth by him is this: If a man throws a spear, the spear will travel. If a man stands at the end of space and throws a spear, the spear will travel. Therefore, there can be no end to the universe.
His argument is unsound, but certainly valid. Valid because the premisises, if thought to be true, are correctly combined with the conclusion, but unsound because the premise (a spear, once thrown, must travel) is untrue. A counter to this analogy would be simply asking him if a man, standing with his toes to a brick wall, throws his spear at the wall; what would happen to the spear? It would not travel any distance greater than the surface of the wall, and so his premise could easily be false. Also, travel is defined by movement through space. If nothing exists beyond the point at which the spear is thrown, not even space, then it cannot travel through it. It'll probably just bounce off, or something equally anti-climactic.
His argument is based on you accepting the premise "if a man throws a spear, it must travel a distance", which sounds perfectly logical, but really is not a sound premise. The argument is brought down by it, but also engenders a greater understanding of the argument by forcing a counter-argument to be logically constructed.