Study Guide: John Locke Definitions and Distinctions:
Proposition: The meaning of a declarative sentence. Propositions are either true or false.
Analytic and Synthetic Propositions:
An analytic proposition is one that is true or false depending upon the concepts involved. E.g., 2 + 2 = 4 is true because of the concepts involved. “Some bachelors are married” is false because of the concepts involved. Thus, these are both analytic propositions.
A synthetic proposition is one that is true or false because of the way the world is. E.g., “It will be colder tonight than last night” and “Idaho is between Washington and Oregon” are synthetic; they are true or false because of the way the world is.
You learn or know a proposition a posteriori if this learning or knowledge depends upon experience. E.g., You know a posteriorithat fire is hot, and that some dogs bite.
You learn or know a proposition a priori if this learning or knowledge does not depend upon experience. E.g., You know that 2 + 2 = 4 and that all bachelors are unmarried without depending upon experience; thus, you know these things a priori.
Although an experience may be the occasion for coming to know these things, this knowledge is still a priori if that experience was not necessary to arrive at that knowledge.
Rationalism and Empiricism: These are philosophical schools of thought that disagree on one point: Is it possible to know a synthetic proposition a priori? In other words, is it possible to know something substantive about the world without having to learn it through experience? The empiricists say no, and the rationalists say yes.
Empiricism: It is NOT possible to know a synthetic proposition a priori.
Rationalism: It IS possible to know a synthetic proposition a priori.
You are indirectly aware of x if you are aware of it only in virtue of being aware of something else. E.g., When you look at a photo of your Uncle Ed, you are indirectly aware of him. (You are aware of him only in virtue of being aware of a photo of him.)
You are directly aware of x when you are aware of the thing itself, without any intermediate stages of awareness. E.g., you are directly aware of your own mental states.
Veil of Perception: This is a metaphorical barrier between you and the world around you. It prevents you from being directly aware of the world, and prevents you from directly comparing your representations of the world with the world itself.
Central question Locke addresses: Is the world really the way it appears to us? That is, do our mental representations of the world match up with the way the world is?
Locke’s answer: Probably. The evidence suggests that our mental representations of the world are accurate, but we cannot be absolutely sure of this.
Primary and Secondary Qualities: Our senses provide us with lots of information about the qualities or properties of objects, but not all of these qualities are “out there” in the objects.
Primary qualities are really “out there.”
These include size, shape, motion/rest, number, and structure.
To change an object’s primary qualities one must alter the object itself.
Secondary qualities are the result of the primary qualities of an object acting upon our sensory systems.
These include color, taste, smell, sound, and feelings of warmth or coldness.
To change an object’s secondary qualities, one may change the object itself, or change the sensory systems of the observer.
Locke’s Inference to the Best Explanation: This is Locke’s argument for the conclusion that our mental representations of the world are generally accurate. He acknowledges that this argument cannot prove that our mental representations are accurate; it only shows that they probably are.
The Causation Thesis: A mental state is a representation of an object only if it was caused by that object.
This separates mental states into those that are representations and those that are not. (The representations are the ones that are caused by the external world.) This rules out hallucinations, etc.
This thesis says nothing about whether these mental representations are accurate. Maybe they are, and maybe they’re not – that’s dealt with in the next step.
The Resemblance Thesis: A mental representation is accurate only if it is caused in the right way.
The Inference to the Best Explanation: This allows one to determine which mental states meet the above conditions (spelled out in the causation and resemblance theses) and are thus accurate representations of the world. This cannot generate proof or certainty; it can only show which mental states probably meet these conditions. Mental states are probably accurate if they are: