Origin 7. New ontological element(s) to be identified. This origin diverges from the reasoning aspects discussed above, focusing instead on the necessity for new conceptual frameworks. The introduction of new ontological elements becomes essential when the current entities of reactivity and mechanism are insufficient. This typically occurs in situations where anomalies reveal fundamental gaps in our understanding that cannot be bridged by merely adjusting existing concepts. The illustrative example chosen is from my previous exploration, where I proposed the idea of identifying a new element and formulating a new concept exactly from attempting to resolve paradoxical reactivities, in particular, quantum mechanical tunneling (QMT) reactivity. QMT, a consequence of the wave nature of particles, implies that a particle can pass through a potential energy barrier without having sufficient energy to overcome it and has recently been found to play significant roles in chemical reactions. QMT reactivity is highly sensitive to the width of the reaction energy barrier. Many studies have reported that while QMT reactivity is strongly influenced by the thermodynamic driving force, substituents, and matrix environments, the observed trends often conflict. Figure illustrates two examples where QMT is responsible for nearly 100% of the overall reactivity, showcasing conflicting trends in QMT reactivity. In Figure (i), both reactions are identity reactions with zero driving force, yet the computed QMT rate constants differ drastically. In Figure (ii), the H-substituted compound exhibits significantly more reactive QMT than the CN-substituted compound in a para-H2 matrix, whereas the results are reversed in a xenon matrix. Noticing that while the Marcus dissection of the reaction barrier height into thermodynamically independent (intrinsic barrier) and dependent (BEP) contributions models the interplay of reaction rate and driving force effectively, a similar concept for barrier width was absent. With that, I defined the intrinsic barrier width (w0) as the barrier width at zero driving force. Analogous to intrinsic barrier heights (that reflect reorganization energy), intrinsic barrier width reflects the reorganization of nuclear coordinates inherent to each family of reactions. This led to the conceptualization of the barrier-width counterpart to the Leffler equation (∆G ‡ = ∆G0 ‡ + α∆G, vide supra), where the barrier width can also be dissected into an intrinsic component that is thermodynamic-independent and a thermodynamic component as per the BEP effect: w = w0+ γ∆G, where γ is analogous to the Brønsted slope, indicating the sensitivity of barrier width to thermodynamic changes. With this new concept, we might be able to rationalize the conflicting trend in Figure (ii). Reactions in the two different solvents (para-H2 or xenon) perhaps belong to different sets of rate-driving force correlation lines, with different intrinsic barrier width w0 and sensitivity of width versus driving force (𝛾). One has smaller barrier width at low driving forces, while the other has smaller barrier width at high driving forces (Figure ). Even though such deconvoluted analysis of barrier width may not resolve all the conflicting trends in reactions where barrier widths are important, it would at least offer a reasonable hypothesis and meaningful guidelines for future endeavors.