   Thus, the De Aspectibus shows that al-Kindî favored an extramission view of vision, in which rays extend from the eyes to make contact with an object, enabling a person to see  it.[2] Following Euclid's Optics ultimately, al-Kindî offers geometrical demonstrations against both the alternative “intromission” view, and the view that fuses extramission with intromission; views identified mostly with Aristotle's De anima and Plato's Timaeus, respectively. In other treatises, however, al-Kindî may be more sympathetic to Aristotle's understanding of vision, mixed with possible familiarity with relevant treatises of Ptolemy and John Philoponus.