Tao is the Way.
Zen is meditation.
These three are one.
Samkhya, Yoga and Vedanta are three of the six orthodox Hindu philosophical systems. Orthodoxy is acceptance of the Veda. Vedanta is the philosophy of the Upanishads, the last part of the Veda.
Samkhya, like non-Vedic Jain philosophy, is soul pluralist. The Yoga Sutras accept the Samkhya philosophy and the two systems form Samkhya-Yoga. However, there are also monistic Vedanta-Yoga syntheses. Neither Vedism nor any philosophical system is necessary for the practice of yoga.
Anarchic Taoism is the antithesis of formalist Confucianism. Zen is Buddhist but it has been argued that Chinese Ch'an/Japanese Zen is a Buddhist-Taoist synthesis.
