Every person claims that he knows something. Our whole live is the great source of gaining knowledge: a person reads books, listens to other people’s opinions and his own intuition and looks at his own experience in life. For centuries great philosophers such as Phaedo, Socrates. Plato, and others argued on questions concerning knowledge. Is it possible to have knowledge at all? Does our knowledge represent reality as it really is?
For every person including myself, gaining knowledge begins with birth. Though some philosophers such as Phaedo say that we had knowledge before that, but we forget it when we are born. And then we just recollect it. Phaedo also discusses perfect justice, beauty, goodness and equality and states that we have never seen these things yet we know they exist. From his point of view knowledge of perfect things must be innate. I cannot agree with this statement. For me your parents, then your teachers and people in your society give you understanding of what is right or wrong, true or false, good or bad. Later you start analyzing everything from your own perspective, deciding what to believe relying on your previous knowledge. This is why I agree to the Socrates point of view. He says that we can distinguish true from false and the standards for that are based on our soul.
At the same time Plato was correct when he said that difference between knowledge and opinion must be rationally justified. For years we are chained in our caves interpreting shadows on the wall as the reality we see. Only if you step out into the wide world where the objects that cast the shadows seem so unfamiliar can you see the world from another perspective. There is no certainty though that this may change your opinion. For example I don’t think that gay marriages are right, it is at variance with the society I grew up in and my religion. And nothing can change my opinion on that, though the whole world around me thinks that is neither good nor bad.
Personally I have several methods of gaining knowledge. From pragmatic point of view I rely upon results, especially time tested results. There are experts in their fields and I think in many cases their observations establish truth. I also believe in God and believe that what God reveals is true. But at the same time if something is logical and consistent, that’s rational and thus is true. Of course the most reliable method for me is rationalism. Knowledge can be deduced from principles that are “indubitable” or true by definition. For example “a whole is always greater than any one of its parts,” “f thing cannot be and not be at the same time in the same respect,” “bachelors are unmarried males” and “triangles have three sides.” These statements are known with certainty to be true because the very meaning of the terms involved (e.g., wholes, parts, things, bachelors, unicorns, triangles) requires that some judgments we make about them do not rely on sense experience. This is why I agree with Plato. He says that sense experience fails to provide us with any guarantee that what we experience is, in fact, true. The information we get by relying on sense experience is constantly changing and often unreliable.
The question of what is human knowledge and if there is any limit to it cannot be answered unambiguously. It cannot be acquired through a single lesson or over a course or two. It requires a lifetime of personal and social experience. We can just add our voice in the row of those trying to answer this question.