"If I knew for a certaintly that a man was coming to my house with the conscious design of doing me good, I should run for my life for fear that I should get some of his good done to me. No, in this case I would rather suffer evil the natural way." Walden; Henry David Thoreau

And some good advice...

Neither a borrower nor a lender be; For loan oft loses both itself and friend, and borrowing dulls the edge of husbandry.

(so says Polonius in Hamlet, Act 1, Scene 3)

And more good advice...

"When you find a big kettle of crazy, it's best not to stir it."

(The 'pointy haired boss', Dilbert, 9/22/09)

And Herbert Spencer said...

"The ultimate effect of shielding men from folly, is to fill the world with fools."