Well, of course you do.
Inventing something, whether it’s as an artist or as a scientist, involves thinking about things that aren’t there.
And that’s pretty much a definition of madness, isn’t it.
Of course that doesn’t mean that inventors all wear straws in their hair, or make ape-noises at the neighbours, or sing love-songs to the daisies.
So I suppose that, on the whole, we'll have to put inventors down as part-time nutters.
I think that most of us would be quite happy with that.