One possible effect of this action, is that the sailor would experience a feeling of happiness, because someone is expressing an interest in his life. The influence an individual has on the future has been mentioned previously in this work,but it warrants further discussion due to its significance. The actual action of submitting your ballot at the polling station is only a part of your potential effect upon election results. This does not end here, because individuals that you have affected go on to sway others. No person is meaningless to humanity.
Every individual affects the future, simply by existing.
The psychological impact upon the parents is obvious, and permanent. Our birth, life, and death all contribute toward the flow of human existence through the way they affect others. The fact that your every action has some level of influence upon the future, means that you are accountable for the effects you indirectly cause. This, of course, applies to eventualities that you could reasonably be expected to foresee. Foresight has more to do with common sense, than intelligence.