difficult to say amar, its like asking is the F word used in -ve or +ve sense? the word is in itself not +ve or -ve but how and what context one says, i can use F word with friends in a +ve way and with someone else in -ve sense..
similarly with cunning, i have used it with friends in a +ve way, and said it in -ve way too...it alll implies to you...
Take another example Is fission reaction+ve or -ve? Can't say right? as it depends how you use it..for making electricity or destroying a nation...
same here...
hope it clarifies the idea...