''There are aspects in this life that are intangible but we accept there existence such as love, empathy, music, abstract art and jazz, humour, the fact that colour doesn't exist, etc.''
I'll just say that these examples are tangible enough that artists (for example) are able to assume that their work is likely invoke feelings of joy, sadness or pleasure...they themselves sharing these feelings.
Colour doesn't exist, but we are able to understand that the brain interprets different wavelengths within the visible range as a colour through a process of recognition and comparison.
