All of our classes here at Still Mind Yoga are open level. That means that the students will be a mixture of day one beginners and seasoned practitioners. Beginners are always welcome to all classes, and all of our teachers are skilled at teaching classes with variations and modifications to accommodate the spectrum of students. The definition of "advanced" vs. "beginner" isn't something that can be defined by one's ability to do physically challenging postures. Also, the focus of the yoga path is on advancement of character and promoting peace, so mixing experienced and inexperienced practitioners makes sense. People who are more developed in terms of peace can be most helpful to the beginners, and kindness to beginners is a core of the practice.
It's an interesting question--how do you define "advanced yogi." In the yoga world at large, it is typically defined by number of years practiced as well as by vigor/challenge of the asana practice. In my experience, it is very difficult to define "advanced" and "beginner." In the Zen tradition, one should always strive to keep a beginner's mind, always fresh and new, and always willing to explore the basics as if for the first time. In the various contemplative traditions I have practiced, learning and re-learning the basics holds something new each time and can be a highly advanced practice. When I got my black belt in Aikido, I was told "now you can finally begin learning." In all spiritual traditions, one should maintain humility and shy away from labeling oneself "advanced."
Yet in the yoga world--one where over 30 million people do yoga in the US alone---we have taken to classifying classes by levels (1, 2, 3...) and assuming the more physically adept classes are the advanced ones. A practical necessity, for sure, but one that misses the complexity of the issue.
Yoga asana---the postures we perform---are but one small part of yoga. There are eight limbs of yoga (a subject too broad to address here in this article). For the sake of brevity, the practice of yoga comprises a holistic path of behavior, connection to Source, understanding of the nature of reality, and discipline of the mind. Discipline of the mind is the foundation upon which everything is built. With an unruly mind, little is possible.
Given the holistic, interconnected, and all-encompassing nature of the path of yoga, how do you classify a student as "advanced" or how do you classify a class as for beginners? One student may be extremely adept at performing asana--perhaps a former dancer or athlete, yet be new to the yamas and niyamas (behavior). Another student may be older after a lifetime of physical rigor and injuries (me!) and be happy keeping it simple. And to further complicate the question, who does the classifying? Who is qualified to assess a student's spiritual level, state of their mind, etc.? It is all too easy to default to what we can see--the outward form of someone's pose--and make assumptions. In our culture that is very competitive and outward-appearance focused, the temptation is very strong to think of the most physically adept student as the most advanced, and assume physical adeptness somehow correlates to being mentally or spiritually advanced (research Ken Wilber's lines of development for much more about this).
My personal philosophy is to avoid these labels as much as possible. Our classes are not classified or leveled and I don't refer to "advanced" versions of poses, just different variations of poses. In my own practice I abstain from classifying others as either advanced or beginner as much as possible. I keep my eyes on my own practice---on my own connection to Source---and I encourage students to do the same. When a student is in a yoga class, their only responsibility is to cultivate that experience of oneness, body and breath as one, thoughts slowing down, peace taking over. I also encourage students to be inwardly guided---to do what their body needs. When I see a student who has had a very tough week going into an early Savasana, or spending more time in child's pose---that is a great thing. Likewise, some students crave physical challenge or vigor, so I always allow time and space for that and am happy when students know their bodies well enough to adjust their practice.
One thing that makes me know that the yoga is taking hold in a student's life beyond simply the asana is how they treat others. When students go out of their way to encourage others, to congratulate students after their first class, or to be helpful to one another---that helps me to see that the yoga is improving people's lives as a whole. We don't come to class to perfect Warrior 2. We practice Warrior 2 so that our lives can improve internally and externally. So that we can become stronger, calmer, happier, more connected to joy, be better parents, spouses, citizens. We practice so that when we are alone with ourselves we are at peace, and when we are with others we can live harmoniously. Given this complex, nuanced, and subtle way that yoga permeates a person's life, it makes labeling and classifying fall far short. How do you define advanced? I prefer to default to one of my favorite teachers (Esther Hicks channeling Abraham) "You never get it done, and you can't get it wrong." By that definition, perhaps we are all beginners and will always be beginners--- and I'm okay with that!