While we're at it... this piece of ruby is about operator precedences. Not strictly in the truthy falsey department but still slightly in topic. The participants are 1, nil, or, ||, assignment and puts ...

  puts (i = nil || 1) => 1
  puts  i => 1
  puts (i = nil or 1) => 1
  puts  i => nil
  puts  i = nil || 1  => 1
  puts  i => 1
  puts  i = nil or 1  => nil
  puts  i => nil