[Vince Ferrer]

Our own civilization does not really produce detectable evidence of its existence that penetrates further than about 0.6c-yr into space. The nearest possible civilization is 7 times further than that; even in a galaxy teaming with planets, the actual nearest civilization could be hundreds of times that far away and still be quite close in interstellar terms. The Fermi paradox isn't really a paradox -- just a question -- for now. It will become a serious issue once we're able to detect signals on the order of 150 c-yr away, provided we continue to see nothing.

The Fermi paradox doesn't depend just upon signals. Many claim an advanced other civilization, if it exists in our galaxy, would have had the time to build a self replicating ship which could visit another star, do some investigation, and build a few copies of itself from raw materials at the new system, which would then go investigate new stars.

This would lead to a geometric increase of stars visited, and the civilization would have had enough time to have visited every star in the galaxy by now.

[FredZarguna]

The Fermi paradox doesn't depend just upon signals.

It actually does. Even millions of ships would have to cover around 3-4 * 10^13 (c-yr)^3 to blanket our galaxy. Our civilization detectable neighborhood is ~1 (c-yr)^3. It would be highly impractical to make a stop on what is beginning to look like ~10^12 planets.