If I can be forgiven I like to use a poker metaphor to describe the difference between investing and speculation. For me investing is where you are dealt a good hand and slowly increase your stake as the hand improves, seeing how the other players react and how the cards are played, speculation is more a bluff, you are dealt a hand and you can take a guess at how good it may be but you cannot see any future cards, however, you bet large on the chance of a big win regardless of the uncertainty. A good poker player (investor) much like in the words of de la Vega, plays a mixture of the two, a mixture of risky bluffs and calculated less risky play.