Evolution seems to have favoured the capacity for empathy (the specks choice) over the capacity for utility calculation, even though utility calculation would have been a 'no brainer' for the brain capacity we have.
The whole concept reminds me of the Turing test. Turing, as a mathematician, just seems to have completely failed to understand that we don't assign rationality, or sentience, to another object by deduction. We do it by analogy.