Peter Smith

Publications, Lectures and Other Stuff

Santorio Santorio (1561-1636)

Santorio Santorio

Santorio Santorio’s father, Antonio Santorio, was a nobleman from Friuli in the service of the Venetian republic; his mother was from a noble family in what is now the Slovenian port-city of Koper, but was then the capital of Venetian Istria (Caput Histriae ‘head of Istria’), where Santorio was born in 1561. He was educated in Koper and later Venice, before entering the University of Padua in 1575, qualifying as a physician in 1582. He was then aged 21. He later spent over a decade serving as personal physician to a Croatian nobleman before setting up a medical practice in Venice in 1599.

In Venice, he became part of the circle of learned men that included his near contemporary Galileo Galilei (1564-1642). Appointed to the chair of theoretical medicine at the University of Padua in 1611, Santorio taught there until his retirement in 1624. He spent the remainder of his life in Venice. He died in 1636.

In treating his patients, Santorio largely followed what was then traditional practice based on the received wisdom of the ancient teachers Hippocrates and Galen, with the idea of health being based on the balance of the body fluids (the ‘humours’), but he also undertook his own research, in which he placed primary reliance on empirical evidence and the use of reasoning rather than traditional authority, thus acting as one of the pioneers of modern science.

In common with others in his scientific circle, Santorio saw the fundamental properties of things as being such qualities as size, number, position and form. This was a radical departure from the traditional ideas of Aristotle and Galen for whom it was the essence of a thing that was important rather than such ‘accidental’ physical properties (What made an apple an apple, or a liver a liver?).

Again, for Santorio, the key metaphor for understanding nature was mechanical rather than the organic metaphor that was central to both Aristotelian natural philosophy and Galenic medicine. Thus, he saw the body as being like a clock, in which the workings were determined by the shapes and positions of its interlocking parts.

He is most famous for his experiments on the weight and metabolism of the body. For this, he devised a ‘metabolic balance’, placing himself on a platform suspended from an arm of a large balance which enabled him to make accurate measurements of changes in his own body weight. He also weighed all his solid and liquid intake and excretions, finding that what he consumed was far heavier in weight than what he excreted. We know now that this difference is accounted for by the expenditure of energy, but Santorio hypothesized that the greatest part of the food he took in was lost from the body through what he called ‘perspiratio insensibilis’ (insensible perspiration). He published his findings in a short book entitled De Statica Medicina (‘Concerning Static Medicine’), which made him famous throughout Europe.

In some cases probably in consultation with Galileo, Santorio was also famous for a number of inventions whereby he was able to measure physical phenomena. These included using a pendulum to measure the human pulse rate (1602) and an early version of what later became the thermometer. Outside of medicine, he invented a wind gauge and meter for measuring a current of water.

The ‘Metabolic Balance’.

See also the entry in the Galileo Project:


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s


This entry was posted on February 22, 2014 by in History of Ideas and tagged , , .
%d bloggers like this: