Dannichu
Tragically unbeyachted.
A point that hasn't been raised yet, though, small dogs are vicious. Large dogs are social.
Not nessisarily; alsatians and dobermans (dobermen? XD) are very anti-social and can be incredibly vicious.
Not all small dogs are vicious, either; spaniels are small and are one of the friendliest breeds out there.
Social dogs can be vicious, too; dalmatians are one of the happiest breeds ever, but attacks by them do some serious damage.