"'A key that can open many locks is called a master key, but a lock that can be opened by many keys is a shitty lock.'”
Ha ha, what a funny joke, right?
That’s a pretty shitty analogy. It only holds if you already accept the conclusion. I can come up with several that make just as much sense, but would lead to different conclusions.
If you have a pencil that can be sharpened by any sharpener, you have a normal pencil; if you have a sharpener that will only sharpen certain pencils, you have a shitty sharpener.
A man who can ride any horse is a cowboy; a horse anyone can ride is a good horse.
A function that can be computed by any machine is a simple function; a machine that can compute any computable function is a Universal Turing Machine.
A man who’ll dance with anyone is fun at a party; A woman who’ll dance with anyone is fun at a party.
A better way for you to have phrased it would have been “look at it this way: ‘ I approve of promiscuous males, and I disapprove of promiscuous females.’”
Emphasis mine. Face it, the joke is only funny if you’re already a misogynist who is against female promiscuity.
And if someone says that to you, and reason is not an option just retort with this:
“Sooo… you’re about two inches long and often found in the hands of authority figures? Sounds about right, from what I’ve heard.”