1. LOCKE 2 An Argument that the External World [the world outside the mind] Exists

2. John Locke 1632-1704 Question: Does this picture prove that Locke existed? Is it evidence that he existed?

3. The Problem The only thing we immediately perceive [or are in any way conscious of] are our own ideas. BUT “Having an idea of X does not prove X exists” (para. 1) [Remember: ideas are, at best, copies of the form of things – like pictures.]

4. Locke’s Main Argument “It is therefore the actual receiving of ideas that gives us notice of the existence of other things, and makes us know…” (para. 2) [Our passivity in perception shows that something else is active.] - even though we don’t know how perception causes ideas

5. Four Supporting Arguments i)“the organs themselves do not produce” ideas (para. 4) ii)“I cannot avoid..having those ideas produced in my mind” (p. 5) iii) since external things can cause pleasure and pain, God gives us “assurance enough” of their existence (para. 3) - “ideas floating in our minds” do not have this power (para. 6) iv) “…I find that the characters that were made at the pleasure of my own thoughts do not obey them…” (para 7)

6. LOCKE versus DESCARTES Descartes, the rationalist mathematician, demands absolute proof before he claims knowledge Locke, the empiricist doctor, does not think that absolute proof is required, and will accept as knowledge whatever is strongly supported by evidence.

7. Locke’s Criterion of Certainty “…the evidence of the senses provide as great a certainty as humans are capable of.” (para. 2): Is this an argument ? Compare: no knowledge of what is not directly seen (para. 9) It is “Folly to expect demonstration in every thing….” (para 10)

8. Corroboration of Sensory Modalities “He that sees a fire may…feel it too” (para. 7) [hear it, etc.] [Objection: that one newspaper agrees with another proves nothing if the question is, ‘Can we trust newspapers?’ Reply: if newspapers disagreed with each other, then we would know we cannot trust them. So if they agree, we have more reason to trust them. (Remember the criterion, 2)]

9. Performative Paradox Argument “…if all be a dream, he [the skeptic] doth but dream that he makes the question, and so it is not much matter that a waking man should answer him…” (para. 8)