Now, a disciple of the noble ones considers this: 'I am not the only one subject to aging, who has not gone beyond aging. To the extent that there are beings — past and future, passing away and re-arising — all beings are subject to aging, have not gone beyond aging.' When he/she often reflects on this, the [factors of the] path take birth. He/she sticks with that path, develops it, cultivates it. As he/she sticks with that path, develops it and cultivates it, the fetters are abandoned, the obsessions destroyed.
The reflection of "I am not the only one subject to..." is repeated for the other 4 reflections. My question is, how is it helpful to know that "I am not the only one" subject to these conditions? How is it of benefit to think about all beings being subject to aging, etc., rather than just oneself? I'm not sure I understand why the reflections on one's own condition were expanded in this way in this sutta. Can anyone shed some light on this?
For reference, I believe the Pali text can be found at http://studies.worldtipitaka.org/tipitaka/16A5/2/2.1/2.1.7.