Can you remember great jokes? I know I can't. Now I know why - the greatest jokes work by subverting usual thought patterns, making them less memorable but funnier, according to the Daily Telelgraph. A final twist and surprise in the joke makes us remember the punchline, but forget the run-up to the gag.

Let's take a little test, shall we?

The Telegraph's example of a bad joke:
What do you call a judge with no thumbs? Justice Fingers.

The Telegraph's example of a "better" joke:
A linguistics professor was lecturing his class one day. "In English", he said, "A double negative forms a positive. In some languages, though, such as Russian, a double negative is still a negative. However, there is no language wherein a double positive can form a negative. A voice from the back piped up, "Yeah, right."

A few of science-flavored jokes:
Why did the statistician cross the interstate? To get data from the other side of the median.
How many academics does it take to change a lightbulb ? None. That's what their students are for.

Did you laugh at those jokes? You aren't alone - four in ten people laugh at bad jokes, while only one in ten groans. And the joke teller can influence the reaction - if you know the joke teller, you are more likely to react directly and negatively to a bad joke, whereas a stranger will respond in a neutral manner.

The article quotes Professor Richard Wiseman, a psychologist from Hertfordshire University, as suggesting people might laugh at bad jokes because they were surprised at receiving such a bad punchline. But that does not explain the curious phenomenon of the Christmas cracker, when people laugh at a bad joke even though they are expecting it, says the article.

[I didn't know what a Christmas Cracker was, so that in itself was a curious phenomenon. Here you go.]

If you didn't laugh at any of those jokes, perhaps it isn't in your genetics.