They’re often a bit cliché, but there are always a few forum signatures that justify their existence with something profound or at least mildly interesting. Here are some of the latter:
“There are no mysteries, only a lack of information.”
“There are no miracles, only unknown scientific facts.”
“The Doors of Wisdom are now open to everyone without exception.”
“The only way forwards is not backwards, unless you’re travelling on a circular path, which on Earth is all but inevitable, unless you’re a flat earther, in which case you’ve lost a dimension and think pizzas are the width of noodles.”
“Two things are infinite: the universe and human stupidity; and I’m not sure about the universe.”
“He who doesn’t want to see is afraid of discovering.”
Okay I admit, they were all transcribed from the same signature except for one which I blatantly made up. I’ll leave as an exercise for the reader to guess which.