title_body: How could my to be constructed language reflect a culture of carefulness?
upvoted_answer: My idea on that would be very close to what you suggested yourself: introducing suffixes / prefixes which would indicate the uncertainty of the word.  For instance, let's suppose that your word for "strong" is hariq, your word for "I sit down" is brumo and your word for "house" is niptug, and the word for "in" or "inside" would be bomp.*
  
  Now I would invent some prefixes, such as ar- meaning "with great certainty," no prefix meaning something along the lines of "a certain degree of certitude, but not absolute certainty," (such as, it is supposed that; it is presumed that) and fun, meaning, "a large amount of uncertainty" (such as "we think" or "it appears possible that")**
  
  Now let us suppose that I want to say that I that I sit down in the house, with an extreme certainty that it was a house that I was sitting in, but the fact that I was sitting or that I am actually inside is assumed to be true, though it could be theoretically disproved.  I would say,
  
  arniptug bomp brumo
  
  
  In this fictive language,
  
  funhariq niptug arbomp brumo
  
  
  would mean, "I sit down in a place definitely inside a house which appears to be strong."
  
  Note that these suffixes / prefixes could theoretically be added to any part of speech, or made different for nouns, verbs, adjectives, interjections, etc.
  
  You could also possibly devise a way to make the order of the words show a carefulness about exactly how accurate what is being said is.
  
  * Words invented totally randomly.
  ** Again, randomly selected; more or less prefixes could be used,
   with different definitions.  This is just an example.