In tantra, for instance, everything is the mandala of the buddha. Some beginners on the tantric path will question or doubt this assertion (although not out loud for fear of breaking the tantric vows). If I am a buddha already, why do I need to cultivate my mind? Although this is true, we need to undergo practice and tame the mind before a state of realization can manifest. Why is that? Because all phenomena are a projection of the mind; when we succeed in taming the mind after diligently staying on the path of practice, we can also affect the world around us. This is likened to watching a slide; the images we see on the screen are a projection of the slides in the projector. In the same way, the external objects that we see are reflections of the habitual tendencies and seeds stored in our mind. Once our mind is pure, all external objects are also pure, we will no longer transmigrate in the cycle of existence.

- Quote from The Logic of Emptiness,"Seeing All External Objects as Phenomena of the Mind"