No, this is how I program all the time. Usually when I start typing I have only a rough idea of what I want to do.<p>But in practice this is not a problem. So what if I don&#x27;t know exactly what type a particular thing will be in the end -- I know generally if it is a number, or an array&#x2F;list, or a hash&#x2F;index... that is all I need to know. I use one of those basic types. If I need to change it later I change it later, and the fact that I am in a statically-typed language is <i></i><i>great</i><i></i> for changes like this because it helps me make them with high confidence.<p>This is why I don&#x27;t believe that anyone who makes this argument in favor of dynamic languages really has that much experience in static languages. The actual outcome in real life is the opposite of what is described.