Fear of Phantoms

Jim was a little more brash, stating that no good model ever accounted for all the facts, since some data was bound to be misleading if not plain wrong. A theory that did/if all the facts would have been carpentered to do this and would thus be open to suspicion. 

An example is provided by the phantom phenomenon of entropy-enthalpy compensation, which attracted the attention and snpport of some of the most able enzymologists during the 1970s, has undermined the scientific value of at least one important book on biochemical adaptation, and is not dead even today. 

Estimation of the enthalpy of activation of a chemical reaction is not very difficult because we know that we are making more energy available as we heat a reaction mixture, and if we determine how much faster it gets as more energy becomes available, it is not particularly hard to convert this into a measure of the enthalpy of activation. Experiment shows that many reactions, whether uncatalyzed or catalyzed by enzymes or other catalysts, increase their rates by about a factor of two for each 10°C increase in temperature, for temperatures around the everyday temperatures at which we live. This could mean that many reactions of all kinds have similar enthalpies of activation, which would have important implications about the sort of events that are taking place at the level of the atoms involved. Flowever, it could also just mean that the reactions that behave in this way are the ones that are easiest to study at convenient temperatures, and if so we may be talking about observer bias rather than anything more fundamental about the world. 

Nonetheless, it is not quite as bad as it sounds, because the detailed theory predicts not a straight-line dependence of rate on temperature, but a straight-line dependence of the logarithm of the rate on the reciprocal of the absolute temperature, that is, on the reciprocal of the temperature above absolute zero, which is at -273°C. Now even if ordinary temperatures are infinitely far from 

Range in which kinetic studies are possible for a typical enzyme 

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N) It was said too that he was frightened of phantoms and demons.] His friends treated this as a fable. .. But it seems that he admitted that he did not like to remain alone, and they allowed it to be implied that he feared assassins. If his philosophy exempted him from the latter but not the former, he still would not have been prevented from feeling uneasy, and one could cite a thought of Horace. " It can be noted in passing that his principles of natural philosophy were not sufficient to remove his fear of apparitions for. 

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