Making an educated guess.
Extrapolating from previous experience and personal knowledge either to predict future events or explain events about which you have no direct knowledge.
"Why did she ignore me just now?"
"I'm justfishing off the bridge here, but I think it's because you didn't call her last time."
Man: Sometimes it's hard to resist the urge to drive right off a fucking bridge HHHhahaha oh look there's one HUUUUhddJSUGYDSDKUHDHGUDBUJWYDYJLAKSJLKDLJSHIDHKNEKBDIFHLSNDBKS
Fogey/fogy /fougi/ sl. (early 18C+, orig. Scot) old-fashioned, stuck-in-the mud.
Person with old fashioned ideas which he is unwilling to change: Come to the disco and stop being such an old fogey!
You think me an old fogeyand an old tory, his thoughtful voice said. I saw three generations since O’Connel’s time. I remember the famine. Do you know that the orange lodges agitated for repeal of the union twenty years before O’Connel did or before the prelates of your communion denounced him as a demagogue? You fenians forget some things. (James Joyce, Ulysses. Penguin Books,1992. p. 38)