I beg to differ, on a technical level electromagnetic radiation can be perceived as a physical force, similar to the sensations felt by an MRI machine. Your counter point appears to be around the emotions blue, or other colours, convey which is actually easier to explain than what a colour actually physically is. We use words to convey emotions all the time and to describe blue, adjectives like calm, cool, cold, sad, open, broad, easy, etc. etc. can be attributed to the colour blue.