Dharmasya Moolam Artha:

To carry out a living in accordance with the Dharma , one needs artha[money ,food,objects of desire,clothes ,and other household articles].Without these dharma cannot be adhered to. Sometimes people like Dronacharya etc resorted to shilonchsvritti [living without asking /begging or taking anything from others] . People observing such complete aparigraha vrata, can eat or support their family by collecting grains left over after cleansing the field. But eventually Drona had to give up this vrata and join royal service as teacher.

Thus even for greats dharma cannot be adhered to without having artha[money].Money forms the basis of all exchanges in the world. Thus one must know how to earn money according to dharma to support dharma of the self. Dharma requires money but dharma cannot be upheld by earning through adharmic means. That means dharma has its moola in satvik artha only,that which has been earned by permissible means. the money thus earned should be employed for dharma which in turns ensures sukha. Money does not directly ensures the sukha but has the intermediary known as dharma.

So a king must know arthashastra to employ the artha towards dharma only.

krishnarpana