for p1 being Point of (TOP-REAL 2)
for a, b, r being Real st p1 in circle (a,b,r) & r > 0 holds
ex p2 being Point of (TOP-REAL 2) st
( p1 <> p2 & p2 in circle (a,b,r) & |[a,b]| in LSeg (p1,p2) )