Just to see, and to be ready to see things with our whole mind, is zazen practice. If we prepare for thinking, there is no need to make an effort to think. This is called mindfulness. Mindfulness is, at the same time, wisdom. By wisdom we do not mean some particular faculty or philosophy. It is the readiness of the mind that is wisdom. So wisdom could be various philosophies and teachings, and various kinds of research and studies. But we should not be attached to some particular wisdom, such as that which was taught by Buddha. Wisdom is not something to learn. Wisdom is something which will come out of your mindfulness. So the point is to be ready for observing things, and to be ready for thinking. This is called emptiness of your mind. Emptiness is nothing but the practice.
~Shunryu Suzuki, in Zen Mind, Beginner's Mind