 However, synchronically (i.e.looking at a single point in time), clines can be seen as an arrangement of forms along imaginary lines, with at one end a 'fuller' or lexical form and at the other a more 'reduced' or grammatical form.What Hopper and Traugott mean is that from a diachronic or historical point of view, changes of word forms is seen as a natural process, whereas synchronically, this process can be seen as inevitable instead of historical.