Pre-moderns recognized two ways that the mind know things – in Latin, intellectus and ratio. Some say it’s the difference between heart-knowledge and head-knowledge, or right-brain vs. left-brain understanding. Intellectus is more of an intuitive, passive understanding, while ratio is more of a logical, active knowledge. Intellectus sees the puzzle and appreciates it as a whole picture. Ratio distinguishes between the pieces of the puzzle and figures out how they all fit together. Intellectus leads to wisdom, ratio to science. Both are necessary for the comprehension of truth.
There are certain things human beings know through intellectus before ratio tries to make sense of it. Every child, for example, knows it is right to play fair, even before being explicitly taught. Every adult knows intuitively the natural law, even when they are denying it due to the selfishness of sin. The problem with modernity is that it paints without a canvas; it lights a fire without a fireplace. It ignores what is given – that which is understood though intellectus – and seeks to create from scratch (ratio without intellectus). While pre-modern wisdom with primitive science sought to understand reality better, modern science without pre-modern wisdom seeks to recreate reality itself.
Like freedom without virtue and technology without morality, a world of ratio without intellectus is a very dangerous place.