I think that Wordsworth's most significant belief in suggesting that there exists an incompatibility between science and poetry was as a response to the Age of Reason's approach to poetic aesthetics.  The Age of Reason which preceded Wordsworth's Romanticism was one in which the poetic art form was highly technical, devoid of what Wordsworth would consider real emotion, and one in which the generalized nature of science impacted artistic development.  By definition, science is a realm that seeks to generalize experience, developing a unifying approach that focuses out individuation.  The conformity that resulted from the Age of Reason's approach to art and poetic development flew directly in the face of Wordsworth's understanding of poetry and its meaning. It is here where Wordsworth feels that science and poetry are opposed to one another.  He does not use the Preface as a chance to bash science.  Rather, he resents how the poetic experience has become so cerebral, so conformist, and devoid of emotional subjectivity, qualities that are more associated with scientific approaches to being.  In his Preface, Wordsworth believes that it is in the individual and unique, singular experience that should be the basis for all poetry.  This particular and differentiated approach to being in the world is what makes poetry come alive.  Contrary to the Age of Reason's cerebral point of view on poetry, Wordsworth argued for an infusion of emotion and spiritual identity with the work.  It is in these two points where Wordsworth ends up rejecting a scientific mentality to poetry and embraces what is decidedly more emotional and more subjective.