Not illustrated by Aristotle; presumed as evident from previous chapters. Recall the eclipse syllogism:
All B is A What has light blocked by the earth cannot cast shadows.
All C is B. The moon has its light blocked by the earth.
All C is A. The moon has a failure to cast shadows.
All B is A Angle in semicircle is one half of two right angles.B (being one half of two right angles) is the material cause of A's (the angle in the semicircle) being C (a right angle). (The middle term is the essence of one or the other of the two terms A or C, but Barnes thinks the text leaves it unclear which.)
All C is B Being one half of two right angles is being a right angle.
All C is A Angle in semicircle is right angle.
C is B. The aggressor is warred uponHere, B (being an aggressor) is the efficient cause of C's being A (of why Athens is warred upon). There was an efficient cause for this--Athens' attack on Persia. Problem: Not a real demonstration (contingent, singular). Barnes' example:
B is A. The Athenians are the aggressor.
C is A. The Athenians are warred upon.
All ducks have webbed feet. C is BHere, Barnes says, "having webbed feet explains why ducks are good swimmers; and the webbing is (ppart of) the efficient expplanation of their swimming prowess." (pp. 229) But is having webbed feet a necessary fact about ducks?
All things with webbed feet are good swimmers and waders. B is A
All ducks are good swimmers and waders. C is A.
C is B He is healthy (i.e. he aims at health).This seems to be Aristotle's later example:
B is A. Healthy is walking. (i.e. health is produced by walking)
C is A. He is walking.
C is B. Walking about means foodstuffs' not remaining on the surface.The idea is supposed to be that the middle term (foodstuffs' not remaining on the surface) is the final cause of C's (walking) having A (being healthy). But this seems wrong: the foodstuffs' behavior CAUSES health in an efficient sense, and health is the final cause of walking. The house example, in Barnes' extrapolation (p. 231):
B is A. Foodstuffs' not remaining on the surface is healthy.
C is A. Walking about after dinner is healthy.
C is B. Shelters for belongings are roofed.
B is A. Houses are shelters for belonging.
C is B. Houses are roofed.
Why does the light shine from the lantern?
Why does it thunder?
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