Actually there were physical and special moves right back to gen I, just not as we know it today. Every move of a particular type was physical or special, depending on the type. EVERY move from types like normal, ghost, ground, rock, fighting, and more were physical (so Hyper Beam was considered physical. This made Chansey possibly the greatest waste of STAB in Pokémon history), and moves from types like fire, water, ice, electric, and so on, were all 'special' (so ice punch, fire punch, and thunder punch were all special. Which is why these moves on Mewtwo, Mew, or even Alakazam using TM's from gen II and transferring back made them broken sweepers)