Everything we think we know is really only perceived by our senses,' he explains patiently. 'The sounds we hear are just waves in the air; colors are electromagnetic radiation; your sense of taste comes from molecules that match a specific area on your tongue. Hey, if our eyes could access the infrared part of the light spectrum, the sky would be green and trees would be red. Some animals see in completely different ways, so who knows what colors look like to them. Nothing is really how we perceive it.