Tools, language, books, agriculture and civilization. These 5 things fit nicely adjacent to one another because each one couldn't have succeeded without the previous, they are all uniquely human inventions.
Remember that humankind thrived just fine without the inventions that you mentioned and arguably they were better off without all the modern things which make life easy. In addition, I think that the best human achievements probably aren't even tangible inventions, they are probably just abstract notions that we take for granted, like compassion, understanding, love, ambition and integrity. For however idealist and untrue you think that is, all humans are endowed with the capacity to achieve all of these things within their lifetime and they are the things that make life bearable and continue to drive the human race forward.