Full Idea
If there were no speech, neither right nor wrong would be known, neither the true nor the false, neither the good nor the bad, neither the pleasant nor the unpleasant.
Gist of Idea
Without speech we cannot know right/wrong, true/false, good/bad, or pleasant/unpleasant
Source
Anon (Upan) (The Upanishads [c.950 BCE], 'Chandogya')
Book Reference
'The Upanishads', ed/tr. Prabhavananda /Manchester [Mentor 1957], p.71
A Reaction
This could stand as the epigraph for the whole of modern philosophy of language. However, the text goes on to say that mind is higher than speech. The test question is the mental capabilities of animals. Do they 'know' pleasure, or truth?