Division is invalidly inferring the quality of the parts from the quality of the whole. It is helpful to think of it as the opposite of the composition fallacy. Composition moves up from parts to whole, and division moves down from whole to parts.
1) Water is wet, so hydrogen and oxygen are wet.
2) I am conscious, so my organs are conscious.
3) The team is great, so each player on the team is great.
4) I am free, so my cells are free.
5) Assuming the universe does not have a cause, it follows that everything in the universe is causeless.
It is important to remember that it is sometimes legitimate to infer the quality of the parts from the quality of the whole. For example, “the whole wall is white so each brick in the wall is white.” Since division is an informal fallacy, you should be sensitive to each case and how the parts and whole are connected in that case.
How to Avoid
Be careful when inferring the qualities of the parts from the qualities of the whole. Sometimes the whole is more than its parts, sometimes it is not. Sometimes it is debatable.
- If the whole is physical, must the parts be physical?
- Create or find a few examples of the division fallacy.
- I do not know. On the surface, it seems this must be the case. However, are the smallest particles physical? How would we know if they weren’t? Leibniz was a philosopher who attempted to reduce all of reality to nonphysical “Monads.”
- See example arguments.