uncertainty vs vanity

uncertainty

noun
  • Doubt; the condition of being uncertain or without conviction. 

  • A parameter that measures the dispersion of a range of measured values. 

  • Something uncertain or ambiguous. 

vanity

noun
  • A dressing table used to apply makeup, preen, and coif hair. The table is normally quite low and similar to a desk, with drawers and one or more mirrors on top. Either a chair or bench is used to sit upon. 

  • Emptiness. 

  • That which is vain, futile, or worthless; that which is of no value, use or profit. 

  • Excessive pride in or admiration of one's own abilities, appearance, achievements, or possessions. 

  • A washbasin installed into a permanently fixed storage unit, used as an item of bathroom furniture. 

How often have the words uncertainty and vanity occurred in a corpus of books? (source: Google Ngram Viewer )