What is knowledge?
In normal conversation we use knowledge to mean:
· Knowing that (facts and information)
· Knowing how (the ability to do something)
Sometimes, we use the word knowledge to mean that we have some information, we know that Mary drinks lemonade, for example. When
we have this type of knowledge then we are able to express it. I cannot say that I know when the Battle of Hastings took place, if I cannot, under any circumstances, say the date! This is not true of knowing how.
If I know how to swim, then when placed in the water I make certain movements and do not sink! However, I may be unable to say how, exactly, I am able to swim. Knowing how does not mean I know that ... If I cannot say the date of the Battle of Hastings, I cannot be said to know it. But if, while swimming, I cannot tell you exactly how I do it, you cannot say I don't know how to swim!
Failing to understand the above can lead us into certain fallacies. If we get instruction from the best public speaker in the world, it does not mean that because he or she can speak excellently, that they know how to instruct others. They might be able to say what they do. For
example they might say how they practice. But this might work for them and not for others! A much less able public speaker, or even one who might never have spoken in public might be a much better teacher. The point is that knowing that and knowing how are two different kinds of knowledge!
In philosophy, knowing that something is the case implies that what is known is true. Can we sensibly say that someone knows something, but it isn't true? We cannot know that something is the case unless we are able to show that it is also true.
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Subject: What is Knowledge? 
