Notes on G.E. Moore's Common Sense

(Originally Written September 6, 2006 in Epistemology)

G.E. Moore - defense of the existence of an external world

Common sense beliefs

1. There is a human body, my body and it had a birth.
2. My body has been in contact or close proximity to earth since its birth.
3. My body is in one place and other things are at a distance from me.
4. There are other human bodies.
5. Therefore, there are objects external to my mind.

Metaphysical solipsism - all that exists is me and my thoughts
Epistemological solipsism - all that I can know is myself and my thoughts

Moore's thoughts "things external to our minds" is synonymous to Kant's "things outside of us"

Realism - The world is mind independent
Idealism - The world is dependent on the mind

Moore is a common sense realist.

Two forms of Realism:

Common sense - no fancy technical philosophy needed or wanted
Critical - technical philosophical proofs offered to support realism

Elements of a rigorous proof

1. The conclusion is different from the premises
2. The conclusion follows from the premises.
3. The premises are known to be true.

When the conclusion follows from premises that are known to be true you have a sound argument.

Moore's proof:

There are two human hands.
Therefore, some objects are external to our minds.

Two major criticisms of Moore:

1) Either Moore's argument is circular or invalid:

If Moore does know that "here is a human hand" then either: he means by this that a human hand exists external to all minds or that he does not mean this. But, if he means this then his argument is circular. If he doesn't mean this, then the conclusion doesn't follow from the premise and is thus, invalid.

2) The idealist objection is - How can he claim that since one thing is external to my mind, it is therefore external to all minds.