What does this tell us about how the people saw the world?

Are you implying that to have an understanding of a concept, that a culture needs to have a word for it? English doesn't have a common word for the German word "schadenfreude" but if I explained that it mean "finding amusement in someone else's pain" then you would immediately grasp the concept.

Surely if an ancient Egyptian was walking around outside vs being bound and gagged in a dark room somewhere, that Egyptian would understand he or she was in a state of "freedom" even if the word wasn't there.

It's surprising how much harder it is to proved a word doesn't exist than that it does :D

Unfortunately, only the 3rd volume of the best dictionary for this (Etymological dictionary of Egyptian Gabor Takacs, 2008) is available online, so I may be back tomorrow when my library opens to revise this. Otherwise, I have been unable to find any individual word for "freedom." Budge's 1920 dictionary does offer the possible usage of the word nefu (elsewhere nfh, etc.), meaning "breath" or "wind," as form of metaphor for freedom. I cannot tell whether or not the verb for "to free" or "to be freed" has a represented noun form.

That being said, michaelthedrunkard's point is important. Significant concepts are often well represented in the culture's vocabulary. Read the Aeneid and you'll see just how much the Romans elevated the virtue of pietas. Read any classic Maya text and you'll see just how important cycles of time were in their cosmology; dates and astronomical tidbits are practically used as punctuation. This doesn't mean that concepts without words are not represented in the worldview: "schadenfreude" is a great example. This is particularly important when considering ancient languages. Most of them we know through specific contexts and regular texts; an absence of a word might just mean that that word is not relevant to our known corpus. For instance, there are single digit instances of the the 1st and 2nd person in Maya hieroglyphs, but thousands of appearances of and a dozen ways to write the third person singular pronoun "u"/"0" (its absolutive case has no grapheme or phoneme in many Maya languages). Does this reflect their culture? Would I be greeted with "Hello CommodoreCoCo! How is CoCo doing today?" Probably not. The majority of texts we have are historic inscriptions proclaiming a 3rd person's accomplishments or labels on jars. You're not gonna get a lot of "you"s on in a dynastic history.

You should also ask the folks over in /r/linguistics!