The underlying nature of our single mind is Buddha nature. If all sentient beings give rise to bodhicitta, the light will shine. Buddhahood is like this light, which is the same anywhere in the world. Clear lights means: if you have love, your mind will be visible and clear, like the space in which a light has been turned on. When there is no bodhicitta, it is like having one electrical source: it will not be sufficient to produce light. Light and enlighten nature of bodhicitta mind have the same essence. There is no distinction. The mind of the Buddhas is bodhicitta, it is empty and compassionate. If you have only emptiness without compassion, there will be no light. If you have both, the light will shine. When emptiness merges with compassion, there is clear light.

-- Garchen Rinpoche