Strange indeed that after twenty years training in colleges and universities man should reach such a station wherein he will deny the existence of the ideal or that which is not perceptible to the senses. Have you ever stopped to think that the animal already has graduated from such a university? Have you ever realized that the cow is already a professor emeritus of that university? For the cow without hard labor and study is already a philosopher of the superlative degree in the school of nature. The cow denies everything that is not tangible, saying, "I can see! I can eat! Therefore, I believe only in that which is tangible!" Then why should we go to the colleges? Let us go to the cow.

‘Abdu’l-Bahá, The Promulgation of Universal Peace, p. 360

The animal is even a greater philosopher, for it attains the ability to do this without labor and study. For instance, the cow denies God and the Holy Spirit, knows nothing of divine inspirations, heavenly bounties or spiritual emotions and is a stranger to the world of hearts. Like the philosophers, the cow is a captive of nature and knows nothing beyond the range of the senses. The philosophers, however, glory in this, saying, "We are not captives of superstitions; we have implicit faith in the impressions of the senses and know nothing beyond the realm of nature, which contains and covers everything." But the cow, without study or proficiency in the sciences, modestly and quietly views life from the same standpoint, living in harmony with nature's laws in the utmost dignity and nobility.

‘Abdu’l-Bahá, The Promulgation of Universal Peace, p. 311-312