If your cat runs in front of you and grabs at your socks as you walk down stairs, do you think he is he just being playful? or trying to trip and kill you?

Depends.

I've had playful cats that loved wrestling socks, and a couple that *were* trying to kill me. Without knowing the cat personally, it's hard to say.

He's probably not trying to kill you. Cats are well aware that they need to keep pet primates around to open cans of cat food.
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But he probably is asking for attention (see, Primates, usefulness as food providers, above).
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My two are across the room right now pretending to be asleep, but I know they're actually plotting out their latest scheme for world domination.
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LOL.

Playfully I find that cats just run under foot alot of the time, either trying to rub on you or play. concidering that they are so well balanced, it probably gives no thought to the idea of you tripping and breaking your kneck falling down the stairs.

actually cats just love to grab onto moving objects when they are playing. my kittens used to hang on my pant legs while I was walking around, so I should know :P

In no way are cats evil...demanding, yes...know how to get their way, YES...but nowhere near evil. A cat treats their humans the same way they're treated. If they are treated with respect and affection, cats give affection back WHEN THEY WANT TO. Cats are semi-independent, and some people don't understand that. I have a cat, and I trust her more than I trust some people I know.

Cats are evil superior beings, my bet is he is trying to trip you into submission.

He is just playing.

He would not want you to die. If you died you couldn't feed him.

oops is telling me -- pet me --- feed me -- or friggin play with me mom.. +5

Oooo. Be careful, be very careful. lol

LOL!!!!No he is just being playful! My cat does it all of the time. It does scare me but I know he is not out to get me.

Drag a string or a toy on a string near you so your cat learns to go for that.

He is probably drunk on the catnip he keeps stealing from the top shelf cabinet above the stove, because that's a real good way to get himself killed.

sure, or welcoming you, or reminding you to feed him or could just be for attention.