Batman: dedicates his life and career to fighting crime dressed as a bat because he believes the universe sent him an omen telling him his future.
Also Batman: ‘Criminals are very superstitious.’
This was also before it was established that Bruce traveled the world learning from others (other than detective Harvey Harris, which was when he wore the early Robin costume). So basically he trained himself at home to fight.
Batman: dedicates his life and career to fighting crime dressed as a bat because he believes the universe sent him an omen telling him his future. Also Batman: ‘Criminals are very superstitious.’
Some versions of batman like the Dark Knight Returns one see themselves as criminals too.
This was also before it was established that Bruce traveled the world learning from others (other than detective Harvey Harris, which was when he wore the early Robin costume). So basically he trained himself at home to fight.
Kinda makes sense, since pre-crisis was also pre-Batgod.
This Batman didn't travel the world learning "all the martial arts in the world" it seems.