Daniel, Isn't that the general idea that Einstein used in his relativity formulation?

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In any case, this thread is kind of split in two. Part of it is a discussion about Sussman using an interpreted language in doing physics and another part is about a specific physics problem.

Addessing the former, I thought I would show what I have been doing in the past few years with Prolog, and specifically the SWIPL distro. The semantic web infrastructure I lean on has incorporated the Notebook paradigm elegantly.

Add the SWISH package and it appears in the menu:

![swish1](http://imageshack.com/a/img923/2989/aVVNPf.png)

Query the knowledgebase using an RDF triple relation, i.e. rdf(Subject,Predicate,Object).

![swish2](http://imageshack.com/a/img924/121/DbA2zv.png)

In this wildcard case, you see query results from the NASA JPL SWEET ontology.

![swish3](http://imageshack.com/a/img923/4536/HodFLk.png)

It handles declarative representations of charts. Format the data structure and the notebook rule will attempt to render it,

![swish4](http://imageshack.com/a/img922/8649/tJGcpF.png)

The same for directed graphs.

![swish5](http://imageshack.com/a/img922/5448/WuUlbb.png)