According to Asko Parpola, the term "dasa" in ancient Indian texts has proto-Saka roots, where "dasa" or "daha" simply means "man". Both "dasa" and "dasyu" are uncommon in Indo-Iranian languages (including Sanskrit and Pali), and these words may be a legacy of the PIE root "*dens-", and the word "saka" may have evolved from "dasa", states Parpola. According to Micheline Ishay – a professor of human rights studies and sociology, the term "dasa" can be "translated as slave". The institution represented unfree labor with fewer rights, but "the supposed slavery in India was of mild character and limited extent" like Babylonian and Hebrew slavery, in contrast to the Hellenic world. The "unfree labor" could be of two types in ancient India: the "underadsatva" and the "ahitaka", states Ishay. A person in distress could pledge themselves for work leading to "underadsatava", while under "ahitaka" a person's "unfree labor" was pledged or mortgaged against a debt or ransom when captured during a war. These forms of slavery limited the duration of "unfree labor" and such a slave had rights to their property and could pass their property to their kin, states Ishay.