It may come as a surprise but my first instrument (excluding my early years) is a guitar. I got away from it for a long time so I could play synths. Despite the fact that I bought a Moog Guitar with MIDI I am really not a big fan of pitch to MIDI. Eventually I would love to buy an Eigenharp Tau but I also line guitars because you can touch the oscillator (the string) and through muting and harmonic techniques change the timbre in more complex ways then are possible on a synth.
What I never really liked about a guitar is it is almost a percussive instrument especially an acoustic. It has a short decay. So all those nice modulation techniques you can do on a synth, are limited on a guitar.
Now after a quick read of the Internet chatter on the Moog Guitar I can see it has been met with much criticism.
Some say it's just a better EBow. Well, first I despise EBows. I never could master using one effectively. EBows also can't take energy away from a string or shift energy between the bridge and the neck shifting harmonic content.
So for me, the Moog Guitar is a very complex oscillator I can touch and has a ladder filter built in to boot. Ok, I realize the filter is a bit gimmicky but I personally like ladder filters and having one built in is a plus and more than window dressing.
Now for the reason I bought one. In a word, sustain. On a guitar there are some tricks to get harmonics but the sustain is limited unless you want to stand in front of a Marshall stack (aka Hendrix). But, if the strings have infinite sustain then a whole world of possibilities opens up based on direct contact with the string. Add processing as you have something unique and with vastly expanded musical girth than a regular guitar.
And since harmonics form the basis of scales and harmony as can be seen from the time of Pythagorus who made his own scale that developed into the western one we us today, it just seems to me that there is rich territory for musical inspiration here.
That, in a nutshell is what I an calling Pythagorus.