Matter is derived from mind or consciousness, and not mind or consciousness from matter.
– Tibetan Book of the Great Liberation

We think the world we see around us is composed of matter–that the stuff of the world is, for the want of a better word, matter stuff. As far as the actual physical reality is concerned, this may be so–uncertain though we may be as to the ultimate nature of this matter stuff. But the world we see around us is not the physical world. The world we actually know is the world that takes form in our mind. And this world is not made of matter stuff, but mind stuff. Everything we know, perceive, and imagine, every color, sound, sensation, thought, and feeling, is a form that consciousness has taken on. As far as this world is concerned, everything is structured in consciousness.

Kant argued that this was even true of space and time. To us, the reality of space and time seems undeniable. They appear to be fundamental dimensions of the physical world, entirely independent of my or your consciousness. This, said Kant, is because we cannot see the world in any other way. The human mind is so constituted that it is forced to construct its experience within the framework of space and time.

SPACE AND TIME ARE NOT, FUNDAMENTAL DIMENSIONS OF AN THE UNDERLYING REALITY.  THEY ARE FUNDAMENTAL DIMENSIONS OF CONSCIOUSNESS.