I have been struck when looking at some of the reading on knowledge that GE Moore yet again provides a very valuable insight into "common sense" approaches to philosophy. In my previous Introduction to Philosophy course I was taken by the "Moorean shift" response to scepticism, and again Moore expresses some important points on epistemology.
By common sense he doesn't just mean "what is commonly believed", it is a little more sophisticated....
Wikipedia explains the "common sense" response well;
"The method of common sense espoused by such philosophers as Thomas Reid and G. E. Moore points out that whenever we investigate anything at all, whenever we start thinking about some subject, we have to make assumptions. When one tries to support one’s assumptions with reasons, one must make yet more assumptions. Since it is inevitable that we will make some assumptions, why not assume those things that are most obvious: the matters of common sense that no one ever seriously doubts.
"Common sense" here does not mean old adages like "Chicken soup is good for colds" but statements about the background in which our experiences occur. Examples would be "Human beings typically have two eyes, two ears, two hands, two feet", or "The world has a ground and a sky" or "Plants and animals come in a wide variety of sizes and colors" or "I right now". These are all the absolutely most obvious sorts of claims that one could possibly make; and, said Reid and Moore, these are the claims that make up common sense.
This view can be seen as either a version of foundationalism, with common sense statements taking the role of basic statements, or as a version of Coherentism. In this case, commonsense statements are statements that are so crucial to keeping the account coherent that they are all but impossible to deny.
If the method of common sense is correct, then philosophers may take the principles of common sense for granted. They do not need criteria in order to judge whether a proposition is true or not. They can also take some justifications for granted, according to common sense. They can get around Sextus' problem of the criterion because there is no infinite regress or circle of reasoning, because