2 posts tagged “presupposition”
I like this particular comic in part because it offers a simple definition of the differences between inductive and deductive reasoning.
Inductive reasoning begins with the conclusion and then seeks data to support that conclusion. Deductive reasoning begins with the data and builds a conclusion.
The artist suggests that deductive reasoning is the method of the scientific establishment, and superior to, that of religious fanatics who start with their dubious outcome and go searching for justification.
The problem with all this is that scientists are just as inductive as religious people. Their starting premise is different in some cases, but they begin with assumptions that cannot be questioned, just like everyone else. These assumptions, like everyone else, form the overall "inductive" character of their inquiry.
Second, even when scientists, or logicians, or philosophers, start down the deductive path, they do so with an inductive commitment to the nature of "facts" as such. Leslie Newbigin grasps this concept well as he explains it in his book, The Gospel in a Pluralist Society:
The development of science as we know it would have been impossible without two beliefs: that the universe is rational and that it is contingent. The point has often been made and hardly needs repeated. If the universe did not have a rational structure, if different instrument readings at different times and places were simply random events which could not be brought into a coherent relation to one another, then science woudl be impossible. But the rationality of science is not something that science can prove; it has to be assumed as a starting point of the scientific effort, and the assumption is a faith commitment.
Not only is he a classicist, and therefore both a student, and a teacher, of the classics, but he brings a wide range of creativity and insight to his theological reflections and life-reflections (not necessarily type-cast theological).
Reading this book, or rereading it, I discovered that Lewis is an able expositor of Presuppositional Apologetics. Before the philosophers run me out of Dodge, keep in mind I'm not making a technical, but a helpful or casual observation.
Here's what I mean: Lewis writes about the possibility of miracles and goes about proving them from something of a rationalist, or even evidentialist approach. I mean, Lewis shows you that miracles are reasonable.
Still, his reasonable appeal stems from his belief that true Reason, true Logic, is back of all that we know and see and experience. Given this, you're either going to presuppose This Logic, or some derivative form or version. Now those are my thoughts, not Lewis's.
He writes ably along these lines, however: "By trusting to argument at all you have assumed the point at issue. All arguments about the validity of thought make a tacit, and illegitimate, exception in favor of the bit of thought you're doing at the moment. It has to be left outside the discussion and simply believed in, in the simple, old-fashioned way. Thus the Freudian proves that all thoughts are due to complexes except the thougths which constitute the proof itself. The Marxist proves that all thoughts result from class-conditioning--except the thought that he's thinking when he says this." (CSL, Miracles, 23)
