Beware: Guitar music theory is a blanket term

There are some concepts that are just too huge and maddening to be seen in any rational light. Guitar music theory is one of them. It's like the blob; it's an intense, soul-sucking, body-destroying jello-like phrase that engulfs everyone who thinks they need to learn it in order to play guitar. 

Many guitar teachers online will tell you that you must learn guitar music theory in order to play guitar. First off, please consider that your enjoyment of guitar is separate from your current understanding of guitar music theory. If you don't know any music theory currently, it doesn't affect your enjoyment of listening to your favorite artist, does it? It doesn't stop you from expressing yourself at a concert of your favorite artist, dancing around and being crazy, does it? Is your expiression of how you feel when you play music hampered in any way by not knowing music theory? I doubt it. 

Consider that the same goes for guitar; You aren't required to know guitar music theory in order to enjoy playing guitar, express yourself, or love every minute of playing music. Want proof? Here's a very short list of guitarists who learned completely by ear and had barely any exposure to music theory:

• Jimi Hendrix
• John Lennon
• Paul McCarthy

There are some guitar teachers who would cry foul at my argument. They would say that these people are the exceptions. Fair enough, but I like to bring them up because it proves that it is possible to learn guitar without learning guitar music theory.

From my perspective as a teacher, and after teaching hundreds of beginners, every single one of them was able to learn how to play and enjoy music without learning music theory at the very beginning. True, some followed up on some topics after they knew how to play, but it's entirely possible to learn to play guitar without it. In many cases, learning music theory slows down the process considerably, especially if it's inappropriate for what a beginner wants to do with the guitar in the first place.

It is a complete and total fallacy, a stale and outdated remnant of antiquated guitar doctrine, that suggests we cannot learn, enjoy, or otherwise play guitar without knowing guitar music theory. It's a total lie! Don't believe it!

Guitar music theory: What's it good for, anyway?

Before you jump decide either way on whether or not to learn guitar music theory, it's not a bad idea to consider if learning it would be appropriate for what you want to do with guitar. After all, guitar music theory is a loaded phrase.

 What we need to do is find the genres of guitar that will be positively affected by you learning guitar music theory, break down the overall term into smaller bite-sized chunks of music theory, and figure out what we need to learn and what we could let go of. Let's jump in:

1. Acoustic Rhythm Guitar. Truth be told, most beginners to guitar are interested in learning the acoustic rhythm guitar style. You don't need to learn any guitar music theory to play this style. Yay!
2. Electric Rhythm Guitar. I think that if you only want to play Nirvana songs or just turn your guitar amp up loud, you might not get very much from learning theory. Go for it if you want, but I'd honestly recommend for you to spend more time learning how to play a lot of tunes. 
3. Fingerpicking Guitar. For the most part, no. You won't need theory to enjoy playing fingerpicking guitar. There might be times that you'll be curious, but unless you are doing superbly advanced fingerpicking, don't worry about it.
4. Rock Lead Guitar. To an extent, rock lead guitar can be affected positively by learning guitar music theory. Specifically, I recommend that you learn guitar scales, and the Nashville number system. That said, keep in mind that plenty of lead guitarists have gone without knowing much about it (read: Jimi Hendrix).
5. Blues Lead Guitar. You'll need to know pentatonic and blues guitar scales very well, and you'll definitely need to know the twelve bar blues form. Otherwise, anything else is a bit of a waste of time.
6. Jazz Guitar. Yes, you will need to learn a lot of guitar music theory to play jazz guitar. You can start by learning guitar music notation, and move onto guitar scales later.
7. Classical Guitar. Classical guitar relies on guitar music notation to transmit the notes to the player; You'll have to learn how to read music. This one skill will lend itself naturally to harmonic analysis later on, especially if you get more interested in performing it.