Locke seems to hold that we have knowledge of the existence of external objects through sensation. Two problems face Locke's account. The first problem concerns the logical form of knowledge of real existence. Locke defines knowledge as the perception of the agreement or disagreement between ideas. However, perceiving agreements between ideas seems to yield knowledge only of analytic truths, not propositions about existence. The second problem concerns the epistemic status of sensitive knowledge: How could the senses yield certain knowledge? This (...) essay argues that the key to solving both problems is Locke's claim that simple ideas are all real, adequate, and true. This explains why, on Locke's view, we have certain knowledge through the senses. It also explains how sensitive knowledge can consist in perceiving an agreement between ideas: perceived agreements among simple ideas of sensation are guaranteed to track relations that obtain among really existing things. (shrink)

Recent advances in neuroscience lead to a wider realm for philosophy to include the science of the Darwinian-evolved computational brain, our inner world producing organ, a non-recursive super- Turing machine combining 100B synapsing-neuron DNA-computers based on the genetic code. The whole system is a logos machine offering a world map for global context, essential for our intentional grasp of opportunities. We start from the observable contrast between the chaotic universe vs. our orderly inner world, the noumenal cosmos. So far, philosophy (...) has been rehearsing our thoughts, our human-internal world, a grand painting of the outer world, how we comprehend subjectively our experience, worked up by the logos machine, but now we seek a wider horizon, how humans understand the world thanks to Darwinian evolution to adapt in response to the metaphysical gap, the chasm between the human animal and its environment, shaping the organism so it can deal with its variable world. This new horizon embraces global context coded in neural structures that support the noumenal cosmos, our inner mental world, for us as denizens of the outer environment. Kant’s inner and outer senses are fundamental ingredients of scientific philosophy. Several sections devoted to Heidegger, his lizard debunked, but his version of the metaphysical gap & his doctrine of the logos praised. Rorty and others of the behaviorist school discussed also. (shrink)

Descartes holds that when you perceive something with perfect clarity, you are compelled to assent and cannot doubt. (This is a psychological claim.) Many commentators read him as endorsing Psychologism, according to which this compulsion is a matter of brute psychological force. I show that, in Descartes’s view, perfect clarity provides a reason for assent—indeed a perfect reason, which precludes any reason for doubt. (This is a normative claim.) Furthermore, advancing a view I call Rational Force, he holds that the (...) normative claim explains the psychological one: since your will is naturally responsive to reasons, you are compelled to assent because you have a perfect reason to assent. This coheres with his view that will is essentially active, self-determined, and free. The force that clarity exerts on the will is not the brute push of an efficient cause, but the rational pull of a final cause. (shrink)

Auguste Comte's doctrine of the three phases through which sciences pass (the theological, the metaphysical, and the positive) allows us to explain what John Stuart Mill was attempting in his magnum opus, the System of Logic: namely, to move the science of logic to its terminal and 'positive' stage. Both Mill's startling account of deduction and his unremarked solution to the Humean problem of induction eliminate the notions of necessity or force—in this case, the 'logical must'—characteristic of a science's metaphysical (...) stage. Mill's treatment had a further surprising payoff: his solution to the Problem of Necessity (what today we call the problem of determinism and freedom of the will). (shrink)