Politician: Now that we are finally cleaning up the industrial pollution in the bay, we must start making the bay more accessible to the public for recreational purposes  Reporter: But if we increase public access to the bay, it will soon become polluted again  Politician: Not true  The public did not have access to the bay, and it got polluted
Ttherefore, if and when the public is given access to the bay, it will not get polluted
If there had been a full moon last night, the tide would be higher than usual today. Since the tide is no higher than usual, there must not have been a full moon last night.