Back when Sonja was still creating toki pona, there used to be another word: pasila. It meant simple, easy. Nowadays, she hardly mentions it at all (unless she’s talking about Brazil). pasila actually never made it to an online release; sonja removed the word from toki pona in 2001 before she published toki pona for the first time. She merged pasila into “pona.”
What does pona mean? Well, we could take a look at the pu definition, or one of the first definitions shared by Sonja. In lipu pu1, the definition of pona is “good, positive, useful; friendly, peaceful; simple.” This definition gives a great list of english words that can all be incorporated into the meaning, but pona in and of itself is positive energy. In toki pona philosophy, things are good when they’re useful, or not too overcomplicated. Because of pasila’s integration into “pona,” that which is “good” is given a more direct meaning. Things that are simple and easy to understand are pona.
But this doesn’t mean that everything that’s complex is ike. complexity can be pona, as long as it’s simple to YOU. I would never describe something I don’t understand as “pona.” But I wouldn’t describe it as ike either. The “simple” in the definition of pona is really what you can explain in simple terms, and that’s what toki pona is all about.
Most proficient speakers agree that “pona” doesn’t directly mean “good.” Many agree that “pona” means “good to me,” and nobody tended to use “simple” in their definition without significant explanation. proficient speakers agree that “simple” in pona is the happy medium in between overcomplicated and oversimplified. the concept of “pona” is integral to toki pona.
toki pona is in fact the result of designing a language to be as pona as possible.