What is the primary foundational emotion / permanent state (स्थायी भाव - Sthayi Bhav) of 'अद्भुत रस' (Adbhut Ras - Wonder/Marvelous sentiment)?

In Indian poetics, each aesthetic flavor or flavor-sentiment (रस) corresponds to a key latent root emotion known as its Sthayi Bhav:
* उत्साह (Energy/Enthusiasm) $\to$ Veer Ras (वीर रस)
* भय (Fear) $\to$ Bhayanak Ras (भयानक रस)
* क्रोध (Anger) $\to$ Raudra Ras (रौद्र रस)
* विस्मय (Astonishment / Surprise / Wonder) $\to$ Adbhut Ras (अद्भुत रस)

Therefore, the permanent emotion of Adbhut Ras is विस्मय.