Tempering untempered chocolate
Tempering chocolate is ensuring melted chocolate has a nice shine and there are a few methods to do that:

add grains of unmelted chocolate and stir (which is the seeding method you're referring to)
let it cool down while stirring
(which is the most labour-intensive method, but the easiest to do if you've never done this before)
which answers all of your questions as now you know what tempering is, how to get out of the chicken-and-egg situation, how to  very first chocolate was ever tempered etc...  :-)

As most chocolate recipes are made by professional Chocolatiers, they don't have time to perform the old tried-and-trusted granny method so they'll tend to use the seeding method...
This is what tempered chocolate should look like:

P.S. If this is the very first time you're making your own chocolates, drop this step entirely: it's just the look and feel that'll change as they will look very professional. (I never temper my chocolate as I only care about the taste and without tempering they'll look like they're &quot;home-made&quot;)  ;-)
P.P.S. There is never any chicken-and-egg situation: if you think any of those situations through till the end you'll realise the egg was first because dinosaurs laid eggs long before there were any chickens! :-)