In An Inquiry Concerning Human Understanding, Hume distinguishes between demonstrative
, or a priori reasoning, and experience, or inductive reasoning, a distinction that I find fascinating. He argues that once you have figured out the math of the circumference of a circle, you know everything you need to know about every circle that ever existed or will exist. "Circle" is a universal, discoverable through reasoning.
He then writes about one billiard ball striking another. Hume argues that one such event cannot tell you anything without multiple repetitions of the same event: inductive reasoning. Of course, math and science (physics) have advanced to the point that we can now make the same kinds of predictions about a billiard ball as we can about a circle. However, we gain that understanding through induction rather than deduction, experience (augmented by scientific instrumentation) rather than reason.
Here's the passage:
"The conclusions which it draws from considering one circle are the same which it would form upon surveying all the circles in the universe. But no man, having seen only one body move after being impelled by another, could infer that every other body will move after a like impulse. All inferences from experience, therefore, are effects of custom, not of reasoning7." (V.1.36)
There's are some interesting word choices in this passage. Notice that "conclusions" about a circle are drawn by "it." The "it" in this passage is reason, knowledge that precedes human understanding, that simply is.On the other hand, "men" infer. We might quibble about distinctions between found and constructed knowledge, particularly since the physics of the billiard ball can eventually be discovered by science.
The last line, though, that "inferences from experience," that is inductive reasoning, is a function of custom rather than reasoning, limits "reasoning" to a very narrow band of knowledge, that which can be known inside the head of the reasoning animal, that needs no outside confirmation. Not sure what to make of this yet, though I keep thinking about Spinoza's Ethics, which is based entirely on reasoning about God.
He then writes about one billiard ball striking another. Hume argues that one such event cannot tell you anything without multiple repetitions of the same event: inductive reasoning. Of course, math and science (physics) have advanced to the point that we can now make the same kinds of predictions about a billiard ball as we can about a circle. However, we gain that understanding through induction rather than deduction, experience (augmented by scientific instrumentation) rather than reason.
Here's the passage:
"The conclusions which it draws from considering one circle are the same which it would form upon surveying all the circles in the universe. But no man, having seen only one body move after being impelled by another, could infer that every other body will move after a like impulse. All inferences from experience, therefore, are effects of custom, not of reasoning7." (V.1.36)
There's are some interesting word choices in this passage. Notice that "conclusions" about a circle are drawn by "it." The "it" in this passage is reason, knowledge that precedes human understanding, that simply is.On the other hand, "men" infer. We might quibble about distinctions between found and constructed knowledge, particularly since the physics of the billiard ball can eventually be discovered by science.
The last line, though, that "inferences from experience," that is inductive reasoning, is a function of custom rather than reasoning, limits "reasoning" to a very narrow band of knowledge, that which can be known inside the head of the reasoning animal, that needs no outside confirmation. Not sure what to make of this yet, though I keep thinking about Spinoza's Ethics, which is based entirely on reasoning about God.
