Democritus' Argument for Atomism

Question 1

Democritus’ Argument for Atomism

Answer 1

1) If there is a body that is not composed of atoms, then it could be divided infinitely many times.
2) If a body could be divided infinitely many times, then either (a) it is composed of points, or (b) it is composed of nothing.
3) (a) is impossible
4) (b) is impossible
5) So, every body is composed of atoms

Question 2

define atom

Answer 2

If x is an atom, x has no proper parts.

Question 3

define proper part

Answer 3

X is a proper part of Y if it is a part of Y and it is not identical to Y

Question 4

explain (1) in Democritus

Answer 4

True by definition of an atom. An atom is something that does not have proper parts. To say that a body is not composed of atoms is to say that it has it has proper parts. Cutting wood example.

Question 5

explain (2) in Democritus

Answer 5

(a) the piece of wood can be seen as a number line - between 0 and x: 0 ____________ x The line is made up of unextended points. We can graph an infinite number of points in the range of this line.

Or

(b), since if you’re not left with points, you’re left with nothing.

Question 6

explain (3) in Democritus

Answer 6

Part of the definition of a point is that it has no magnitude. Democritus argues that it is impossible for any amount of things which have no magnitude to come together and make up something which has magnitude.

Question 7

explain (4) in Democritus

Answer 7

It is impossible for something with magnitude to be composed of non existing things, it simply doesn’t make any sense.

Question 8

the pointy objection

Answer 8

• There are things which we clearly see as existing, such as lines, that are made up of an infinite number of points which have no magnitude.
• If lines are possible, then it is not impossible for a body to be composed of points and premise (3) is wrong.

Question 9

outline for democritus

Answer 9

1) define atom
2) define proper part
3) explain all premises
4) the pointy objection