# Euclidean Geometry in Classical Thought - Used for Realization or Representation?

I posted this in the Physics.SE Forum but I figured I'd ask this here as well since it's relevant to the forum subject :]

Taken from John J. Roche's "The Mathematics of Measurement: A Critical History":

When physico-mathematicians in the seventeenth century needed to represent their physical quantities mathematically they almost always turned to geometry rather than to numbers.

The author goes on to explain this further, saying how the Ancient Greeks had used geometrical figures to represent physical quantities rather than numbers (influencing the physicists later on) and how they were most appropriate for representation since they denoted "continuous physical quantities".

Is the author saying that physicists and mathematicians realized physical relationships geometrically? Or is he just saying that they merely chose to represent physical quantities and their relationships to others with geometrical figures? It seems extremely non-intuitive to view physical quantities as being segments/planes/solids instead of as quantifiable values with defined dimensions. Of course it's easier to view/realize proportionalities between physical quantities through geometrical/graphical means, but there must have been a numerically-based intuition even before this. In other words in finding a relationship between 2 quantities, there must have been a numerically-based line of thought that preceded a geometrical demonstration of it, simply through my reasoning that it is more intuitive.

Also, what makes physical quantities continuous? Wouldn't you figure them to be discrete considering that they are quantified by units?

Here's a direct link to the book I'm referring to (Google Books). The quote stated above is on page 87, and it continues on from there.

Any input/corrections on this is greatly appreciated and encouraged! :]

Thank you!

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