lie vs lay - help please!

[thumbwitch]

never mind the vocab, someone please help with the grammar!
"there are myriad diseases whose aetiologies lie in complex networks"

Should it be lie? Or should it be lay because it's a plural? Lie looks more right but I need to be sure...

I think lie (although heaven only knows what the sentaence means!). Lay is the past form of lie isn't it? You're speaking in the present tense.

I would say lie. The diseases lie, they don't lay.

that's what I thought - ta lots!

Or more passive- I got laid etc

Amiccisima's right. It's lie in your example. DP seems to get it wrong every day ("Are you going to lay down?" to DD). It drives me up the wall!