I discuss various direct calculations of the properties of the one-band
Hubbard model on a square lattice and conclude that these properties
sufficiently resemble those of the cuprate superconductors that no more
complicated interactions are necessary to cause high Tc superconductivity.. In
particular, I discuss phonon effects and conclude that these may be effective
in reducing Tc and the gap in electron-doped materials.Comment: 4 pages, 2 figure