Did Werner's theory replace all earlier valence ideas?
A common misconception is that I discarded all prior valence theory. I did not. I built upon the concept of valence as understood for simple compounds—what I called primary valence—and extended it to explain coordination compounds. My theory did not replace Kekulé's or Couper's ideas for organic molecules; it complemented them by introducing secondary valence for metals. Some critics, like Sophus Jørgensen, argued that my chain theory of ammonia-metal bonds was unnecessary, but my isomer counts and optical resolutions proved them wrong. My work also did not immediately explain bonding in terms of electrons—that came later with Lewis and Pauling. What I provided was a geometric framework: the coordination number and spatial arrangement. The octahedron, tetrahedron, and square plane became the new alphabet of inorganic chemistry. So, no—I did not overthrow all earlier ideas; I expanded them into a third dimension.
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