Hand-waving

I need exact figures, not hand-waving and guesses.

Source: tatoeba (6983459)

So when we're discussing thought and conscious processes, talking about minds is precise, and even measurable (what else do public opinion pollsters do?) while talking about brains is just hand-waving.

Source: wiktionary

For years much of this has been explained with hand-waving references to body types and metabolism—broadly accurate, but cold comfort to the estimated 61% of Americans who are overweight or obese and want to have their weight controlled, not merely explained.

Source: wiktionary

You, me and everything in the universe are holograms. This may seem very vague and hand-waving. However, in 1998, the Argentinean-American physicist Juan Maldacena published a paper that shored up the idea that we live in a ‘holographic universe’ and set the world of physics alight.

Source: wiktionary