Retrospectively, Professor Siwel did Quite well with his follow-up representation, Currently utilized by generation X.

The first clue given was: "A clue, the only uppercase letters that you need to take note of is Professor Siwel. He is a real person."

Second Clue: Professor lewis invented a diagram, that clue is only for the first line of the riddle. Theres more, think further....

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    – Rubio
    Jul 12, 2017 at 23:31

2 Answers 2


Some wild speculation:

Professor Lewis invented a diagram

Professor Lewis and his diagrams refers obviously to [Lewis Dot Diagrams], which involve the depiction of molecules and compounds.1

the only uppercase letters that you need to take note of is Professor Siwel

These are P and S. Based on the reference to Lewis diagrams, I suppose these might be referencing Phosphorus and Sulfur, or some compound of the two. This leads to Phosphorus Sulfides, which have multiple different applications.

Currently utilized by generation X.

Among the few uses of Phosphorus Sulfides are Parathion, Malathion, matches, and as parts of electrolytes for Lithium batteries. Generation X is generally considered to be those born between ~1965 and ~1985, which means that they currently are 40-60 years of age. Parathion and Malathion are pesticides, and there's nothing to support that they'd be used in particular by Generation X. Likewise, matches and lithium batteries are used very widely, not just by the 40-60 age group.

Is there any more context you can give at all for the question?



As noted by Luke Bickell, the diagram invented by Professor Lewis is likely

The Lewis Dot Diagram

Desperately trying to recall high school chemistry, these don't capture

Chirality (left- or right-handedness of molecules). From Wikipedia: "A chiral molecule/ion is non-superposable on its mirror image." These molecules are denoted R-blah & S-blah and are called enantiomers or optical isomers.

So we may be able to interpret Siwel and Lewis as some kind of nod to this.

Basic examples of chirality often feature a carbon atom with four covalent bonds, thus forming an X-shaped diagram. Note that X (chi) is also the first letter of chiral in Greek.

A follow-up representation which visualises the described differences is the

Fischer Projection


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