Postmodern Beatnik wrote:
Here is the complete quote:

"For let me tell you, gentlemen, that to be afraid of death is only another form of thinking that one is wise when one is not; it is to think that one knows what one does not know. No one knows with regard to death whether it is not really the greatest blessing that can happen to a man, but people dread it as though they were certain that it is the greatest evil, and this ignorance, which thinks that it knows what it does not, must surely be ignorance most culpable."

The point is not that one can only be afraid of death if one knows what it is -- after all, this is blatantly false. Instead, Socrates is asserting that there is no rational reason to be afraid of something when you don't know if it is good or bad. More specifically, he is saying that it is irrational to treat death as a certainly bad thing when it is not certain at all whether or not death is good or bad. It might be rational to wonder about and hope against the possibility that death will be bad, but acting as if we have knowledge that we do not have makes no sense.

What Socrates is getting at becomes clearer when we understand that the statement is part of his explanation as to why he will accept death if convicted of crimes against Athens. Here is what he says a sentence later:

"But I do know that to do wrong and to disobey my superior, whether God or man, is wicked and dishonorable, and so I shall never feel more fear or aversion for something which, for all I know, may really be a blessing, than for those evils which I know to be evils."

So we have something that may be good or bad balanced against something we (putatively) know to be wrong. This choice, Socrates thinks, should be an easy one. As we should never do anything that is wrong, we must choose the other path -- regardless of whether or not it is pleasant for us personally.