Eye-blinking is a visible involuntary action. Sneezing. Coughing. Of course, most physiological actions like heartbeat, peristalsis, healing, etc., etc. Are also involuntary.
2/4 equals one-half. One half of anything is 50%.
Dorothy Vining
I am an old lady with a lot of curiosity. Don't know exactly how Blurtit works yet, but will in due time I guess.