careful vs unguarded

careful

adj
  • Taking care; attentive to potential danger, error or harm; cautious. 

  • Conscientious and painstaking; meticulous. 

unguarded

adj
  • Displaying a lack of caution or thought. 

  • Having no guard or protection; vulnerable. 

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