Encodes scale — large, small, vast, microscopic.
What It Does
Number.Magnitude neurons encode the relative scale of quantities rather than their specific values. They activate on scale descriptors: 'enormous', 'microscopic', 'colossal', 'negligible', 'astronomical'. They also fire on implicit scale — 'the entire population of China' carries a Magnitude signal even without a numeral. These neurons process quantity as a qualitative dimension rather than a precise count.
How It Behaves
Magnitude neurons show a distinctive middle-to-late layer concentration. Scale is a conceptual abstraction that requires context to evaluate — whether 'a million dollars' is a large or small amount depends entirely on what is being purchased. This context-dependence means Magnitude neurons must wait for more semantic information before activating fully, pushing their peak to later in the processing pipeline.
Research Example
In Gemma 2B, Number.Magnitude neurons fire on 'a single atom of carbon' and 'the entire Milky Way galaxy' with opposite polarity — one is minimal scale, one is maximal. The Magnitude signal is inverted, not just differing in intensity. Models that confuse scale (e.g., mixing up millimeters and kilometers in unit conversion) show characteristic Magnitude neuron suppression at the point of confusion.