We give here a new proof of Erdos-Rado canonizing theorem for pairs
which yields the upper bound 2^{(3/2).m^6} in the finite case. The
proof evolved naturally from a new proof of Ramsey theorem for pairs which
we present too.
Remark:
H. Lefmann and V. Rodl proved much better upper bound 2^{c.m^2.log m} (Combinatorica 15 (1995), 85-104; see also J. Comb. Theory, Ser. B 58 (1993), 1-13). For the best upper bound for k-tuples see S. Shelah (Comment. Math. Univ. Carol. 37 (1996), 445-456).